DC HEARING AID DISPENSER EXAM 2026/2027 | 150 Practice VERIFIED
QUESTIONS & ANSWERS | DC HEALTH BOARD OF AUDIOLOGY LICENSE PREP |
INSTANT DOWNLOAD .
SECTION 1: AUDITORY ANATOMY AND PHYSIOLOGY (Questions 1–25)
1. Which structure of the ear is primarily responsible for converting mechanical sound vibrations into
electrical nerve impulses?
A. Tympanic membrane
B. Cochlea
C. Ossicles
D. Pinna
Answer: B
Rationale: The cochlea, located in the inner ear, contains the organ of Corti with hair cells that
transduce mechanical vibrations (hydraulic energy) into electrical signals (action potentials) along the
auditory nerve. The tympanic membrane and ossicles are involved in mechanical impedance matching,
and the pinna collects sound.
2. The middle ear ossicles are arranged in which order from the tympanic membrane to the oval
window?
A. Stapes, incus, malleus
B. Malleus, incus, stapes
C. Incus, stapes, malleus
D. Malleus, stapes, incus
Answer: B
Rationale: The three ossicles are the malleus (attached to the tympanic membrane), incus (middle),
and stapes (attached to the oval window). This chain amplifies and transmits vibrations from the
eardrum to the inner ear.
3. What is the primary function of the Eustachian tube?
A. To amplify high-frequency sounds.
B. To equalize pressure between the middle ear and the atmosphere.
C. To transmit sound to the inner ear.
D. To produce cerumen.
,Answer: B
Rationale: The Eustachian tube connects the middle ear cavity to the nasopharynx, allowing for
pressure equalization and drainage of middle ear secretions. Dysfunction can lead to middle ear
pathology such as otitis media.
4. Which part of the auditory system is responsible for localization of sound in the horizontal plane?
A. Cochlea
B. Superior olivary complex
C. Inferior colliculus
D. Medial geniculate body
Answer: B
Rationale: The superior olivary complex in the brainstem is the first site of binaural convergence and is
critical for processing interaural time and intensity differences, which are the primary cues for horizontal
sound localization.
5. The phenomenon of "upward spread of masking" refers to:
A. Low-frequency sounds masking high-frequency sounds more effectively than the reverse.
B. High-frequency sounds masking low-frequency sounds more effectively than the reverse.
C. Masking that occurs only in the presence of background noise.
D. The inability to localize sound in the vertical plane.
Answer: A
Rationale: Upward spread of masking occurs because the traveling wave on the basilar membrane is
broader for low-frequency sounds. Consequently, a low-frequency masker can effectively mask a higher-
frequency signal, but a high-frequency masker has less effect on a lower-frequency signal.
6. Which type of hearing loss is characterized by a problem in the outer or middle ear that reduces the
efficient transfer of sound to the inner ear?
A. Sensorineural hearing loss
B. Conductive hearing loss
C. Mixed hearing loss
D. Central auditory processing disorder
Answer: B
Rationale: Conductive hearing loss results from pathology in the outer or middle ear (e.g., cerumen
impaction, ossicular discontinuity, otitis media) that impedes sound conduction. Sensorineural loss
involves the cochlea or auditory nerve.
,7. Presbycusis is best described as:
A. Hearing loss caused by occupational noise exposure.
B. Age-related hearing loss, typically affecting high frequencies.
C. A congenital hearing loss present at birth.
D. Hearing loss caused by ototoxic medications.
Answer: B
Rationale: Presbycusis is the most common form of sensorineural hearing loss, resulting from age-
related degeneration of cochlear structures. It typically presents as bilateral, symmetrical high-
frequency loss.
8. The acoustic reflex involves the contraction of which muscles?
A. Tensor tympani and stapedius
B. Malleus and incus
C. Levator veli palatini and tensor veli palatini
D. Orbicularis oculi and buccinator
Answer: A
Rationale: The acoustic (or stapedial) reflex is mediated by the contraction of the stapedius muscle
(and to a lesser extent, the tensor tympani) in response to intense sound, stiffening the ossicular chain
and reducing sound transmission to the inner ear.
9. Which structure separates the middle ear from the inner ear?
A. Tympanic membrane
B. Oval window
C. Round window
D. Eustachian tube
Answer: B
Rationale: The oval window is the membrane-covered opening between the middle ear and the
vestibule of the inner ear. The stapes footplate sits in the oval window, transmitting vibrations to the
cochlear fluids. The round window is a separate opening that allows for fluid displacement.
10. A patient presents with a "conductive" hearing loss. Which of the following is a likely cause?
A. Acoustic neuroma
B. Noise-induced hearing loss
C. Cerumen impaction
D. Ototoxicity
, Answer: C
Rationale: Cerumen impaction in the external auditory canal is a common and reversible cause of
conductive hearing loss. Acoustic neuroma, noise-induced loss, and ototoxicity typically cause
sensorineural hearing loss.
11. What is the primary role of the pinna?
A. To transduce sound into electrical signals.
B. To collect and funnel sound into the ear canal and assist with localization.
C. To equalize middle ear pressure.
D. To amplify low-frequency sounds.
Answer: B
Rationale: The pinna (auricle) is the visible part of the outer ear. Its irregular shape helps collect sound
waves and funnel them into the ear canal. It also plays a role in sound localization, particularly in the
vertical plane and in distinguishing front from back.
12. The traveling wave on the basilar membrane is initiated by:
A. Movement of the tympanic membrane.
B. Vibration of the stapes footplate in the oval window.
C. Contraction of the stapedius muscle.
D. Fluid movement in the semicircular canals.
Answer: B
Rationale: The inward and outward movement of the stapes footplate in the oval window creates
pressure waves in the cochlear fluids. These pressure waves cause the basilar membrane to vibrate in a
frequency-specific pattern known as the traveling wave.
13. Which of the following is a sign of a sensorineural hearing loss?
A. Air conduction thresholds are worse than bone conduction thresholds.
B. Bone conduction thresholds are normal, but air conduction is abnormal.
C. Air and bone conduction thresholds are both abnormal and within 10 dB of each other.
D. A large air-bone gap.
Answer: C
Rationale: In sensorineural hearing loss, both air and bone conduction thresholds are elevated because
the pathology is in the inner ear or neural pathway. The air-bone gap (difference between air and bone
thresholds) is typically 10 dB or less. An air-bone gap indicates a conductive component.
QUESTIONS & ANSWERS | DC HEALTH BOARD OF AUDIOLOGY LICENSE PREP |
INSTANT DOWNLOAD .
SECTION 1: AUDITORY ANATOMY AND PHYSIOLOGY (Questions 1–25)
1. Which structure of the ear is primarily responsible for converting mechanical sound vibrations into
electrical nerve impulses?
A. Tympanic membrane
B. Cochlea
C. Ossicles
D. Pinna
Answer: B
Rationale: The cochlea, located in the inner ear, contains the organ of Corti with hair cells that
transduce mechanical vibrations (hydraulic energy) into electrical signals (action potentials) along the
auditory nerve. The tympanic membrane and ossicles are involved in mechanical impedance matching,
and the pinna collects sound.
2. The middle ear ossicles are arranged in which order from the tympanic membrane to the oval
window?
A. Stapes, incus, malleus
B. Malleus, incus, stapes
C. Incus, stapes, malleus
D. Malleus, stapes, incus
Answer: B
Rationale: The three ossicles are the malleus (attached to the tympanic membrane), incus (middle),
and stapes (attached to the oval window). This chain amplifies and transmits vibrations from the
eardrum to the inner ear.
3. What is the primary function of the Eustachian tube?
A. To amplify high-frequency sounds.
B. To equalize pressure between the middle ear and the atmosphere.
C. To transmit sound to the inner ear.
D. To produce cerumen.
,Answer: B
Rationale: The Eustachian tube connects the middle ear cavity to the nasopharynx, allowing for
pressure equalization and drainage of middle ear secretions. Dysfunction can lead to middle ear
pathology such as otitis media.
4. Which part of the auditory system is responsible for localization of sound in the horizontal plane?
A. Cochlea
B. Superior olivary complex
C. Inferior colliculus
D. Medial geniculate body
Answer: B
Rationale: The superior olivary complex in the brainstem is the first site of binaural convergence and is
critical for processing interaural time and intensity differences, which are the primary cues for horizontal
sound localization.
5. The phenomenon of "upward spread of masking" refers to:
A. Low-frequency sounds masking high-frequency sounds more effectively than the reverse.
B. High-frequency sounds masking low-frequency sounds more effectively than the reverse.
C. Masking that occurs only in the presence of background noise.
D. The inability to localize sound in the vertical plane.
Answer: A
Rationale: Upward spread of masking occurs because the traveling wave on the basilar membrane is
broader for low-frequency sounds. Consequently, a low-frequency masker can effectively mask a higher-
frequency signal, but a high-frequency masker has less effect on a lower-frequency signal.
6. Which type of hearing loss is characterized by a problem in the outer or middle ear that reduces the
efficient transfer of sound to the inner ear?
A. Sensorineural hearing loss
B. Conductive hearing loss
C. Mixed hearing loss
D. Central auditory processing disorder
Answer: B
Rationale: Conductive hearing loss results from pathology in the outer or middle ear (e.g., cerumen
impaction, ossicular discontinuity, otitis media) that impedes sound conduction. Sensorineural loss
involves the cochlea or auditory nerve.
,7. Presbycusis is best described as:
A. Hearing loss caused by occupational noise exposure.
B. Age-related hearing loss, typically affecting high frequencies.
C. A congenital hearing loss present at birth.
D. Hearing loss caused by ototoxic medications.
Answer: B
Rationale: Presbycusis is the most common form of sensorineural hearing loss, resulting from age-
related degeneration of cochlear structures. It typically presents as bilateral, symmetrical high-
frequency loss.
8. The acoustic reflex involves the contraction of which muscles?
A. Tensor tympani and stapedius
B. Malleus and incus
C. Levator veli palatini and tensor veli palatini
D. Orbicularis oculi and buccinator
Answer: A
Rationale: The acoustic (or stapedial) reflex is mediated by the contraction of the stapedius muscle
(and to a lesser extent, the tensor tympani) in response to intense sound, stiffening the ossicular chain
and reducing sound transmission to the inner ear.
9. Which structure separates the middle ear from the inner ear?
A. Tympanic membrane
B. Oval window
C. Round window
D. Eustachian tube
Answer: B
Rationale: The oval window is the membrane-covered opening between the middle ear and the
vestibule of the inner ear. The stapes footplate sits in the oval window, transmitting vibrations to the
cochlear fluids. The round window is a separate opening that allows for fluid displacement.
10. A patient presents with a "conductive" hearing loss. Which of the following is a likely cause?
A. Acoustic neuroma
B. Noise-induced hearing loss
C. Cerumen impaction
D. Ototoxicity
, Answer: C
Rationale: Cerumen impaction in the external auditory canal is a common and reversible cause of
conductive hearing loss. Acoustic neuroma, noise-induced loss, and ototoxicity typically cause
sensorineural hearing loss.
11. What is the primary role of the pinna?
A. To transduce sound into electrical signals.
B. To collect and funnel sound into the ear canal and assist with localization.
C. To equalize middle ear pressure.
D. To amplify low-frequency sounds.
Answer: B
Rationale: The pinna (auricle) is the visible part of the outer ear. Its irregular shape helps collect sound
waves and funnel them into the ear canal. It also plays a role in sound localization, particularly in the
vertical plane and in distinguishing front from back.
12. The traveling wave on the basilar membrane is initiated by:
A. Movement of the tympanic membrane.
B. Vibration of the stapes footplate in the oval window.
C. Contraction of the stapedius muscle.
D. Fluid movement in the semicircular canals.
Answer: B
Rationale: The inward and outward movement of the stapes footplate in the oval window creates
pressure waves in the cochlear fluids. These pressure waves cause the basilar membrane to vibrate in a
frequency-specific pattern known as the traveling wave.
13. Which of the following is a sign of a sensorineural hearing loss?
A. Air conduction thresholds are worse than bone conduction thresholds.
B. Bone conduction thresholds are normal, but air conduction is abnormal.
C. Air and bone conduction thresholds are both abnormal and within 10 dB of each other.
D. A large air-bone gap.
Answer: C
Rationale: In sensorineural hearing loss, both air and bone conduction thresholds are elevated because
the pathology is in the inner ear or neural pathway. The air-bone gap (difference between air and bone
thresholds) is typically 10 dB or less. An air-bone gap indicates a conductive component.
