National Board of Examiners in
Optometry (NBEO) Questions And
Correct Answers (Verified Answers) Plus
Rationales 2025/2026 Q&A | Instant
Download Pdf
1. Which of the following is the primary neurotransmitter in
parasympathetic innervation of the eye?
A) Dopamine
B) Norepinephrine
C) Acetylcholine
D) Serotonin
Parasympathetic innervation of the eye uses acetylcholine to stimulate
muscarinic receptors on the sphincter pupillae and ciliary muscle.
2. The most common cause of sudden, painless monocular vision loss in
adults over 50 is:
A) Retinal detachment
B) Central retinal artery occlusion
C) Optic neuritis
D) Vitreous hemorrhage
Central retinal artery occlusion typically presents as sudden, painless
vision loss with a pale retina and cherry-red spot at the fovea.
3. Which corneal layer regenerates most readily after injury?
A) Endothelium
B) Epithelium
C) Bowman's layer
D) Descemet’s membrane
The corneal epithelium has a high regenerative capacity due to basal
epithelial stem cells.
4. In refractive error, a negative spherical lens is used to correct:
A) Hyperopia
B) Myopia
, C) Astigmatism
D) Presbyopia
Myopia causes light to focus in front of the retina, and negative lenses
diverge light to bring focus onto the retina.
5. Which photoreceptor is responsible for color vision under bright light?
A) Rods
B) Cones
C) Ganglion cells
D) Bipolar cells
Cones mediate photopic (bright light) vision and are sensitive to red,
green, and blue wavelengths.
6. A patient presents with a painful red eye, photophobia, and small
hypopyon. The most likely diagnosis is:
A) Viral conjunctivitis
B) Bacterial keratitis
C) Allergic conjunctivitis
D) Episcleritis
Bacterial keratitis often presents with pain, photophobia, discharge, and
a localized infiltrate with possible hypopyon.
7. Which ocular structure develops from the surface ectoderm?
A) Retina
B) Optic nerve
C) Lens
D) Choroid
The lens originates from the surface ectoderm; the retina and optic nerve
develop from neural ectoderm.
8. The most common form of color vision deficiency is:
A) Blue-yellow
B) Complete achromatopsia
C) Red-green
D) Tritanopia
Red-green deficiencies, including protan and deutan defects, are the
most common inherited color vision defects.
9. Which intraocular pressure-lowering drug works by increasing aqueous
outflow through the uveoscleral pathway?
, A) Timolol
B) Latanoprost
C) Dorzolamide
D) Brimonidine
Prostaglandin analogs like latanoprost increase uveoscleral outflow,
effectively reducing IOP.
10.A patient’s visual field shows a right homonymous hemianopia. The
lesion is likely located in the:
A) Right optic nerve
B) Optic chiasm
C) Left optic tract
D) Left retina
A right homonymous hemianopia indicates loss of the same visual field in
both eyes, typically due to a lesion in the contralateral optic tract.
11.The primary component of the vitreous humor is:
A) Collagen type I
B) Elastin
C) Water
D) Glycosaminoglycan
The vitreous is 98–99% water, with a collagen framework providing
structural support.
12.Which bacteria is most commonly associated with bacterial
conjunctivitis in children?
A) Haemophilus influenzae
B) Pseudomonas aeruginosa
C) Staphylococcus aureus
D) Streptococcus pneumoniae
Haemophilus influenzae is a leading cause of acute bacterial
conjunctivitis in children.
13.The fovea contains:
A) Rods only
B) Cones only
C) Rods and cones
D) Ganglion cells only
The fovea is specialized for high acuity and color vision, containing
densely packed cones without rods.
Optometry (NBEO) Questions And
Correct Answers (Verified Answers) Plus
Rationales 2025/2026 Q&A | Instant
Download Pdf
1. Which of the following is the primary neurotransmitter in
parasympathetic innervation of the eye?
A) Dopamine
B) Norepinephrine
C) Acetylcholine
D) Serotonin
Parasympathetic innervation of the eye uses acetylcholine to stimulate
muscarinic receptors on the sphincter pupillae and ciliary muscle.
2. The most common cause of sudden, painless monocular vision loss in
adults over 50 is:
A) Retinal detachment
B) Central retinal artery occlusion
C) Optic neuritis
D) Vitreous hemorrhage
Central retinal artery occlusion typically presents as sudden, painless
vision loss with a pale retina and cherry-red spot at the fovea.
3. Which corneal layer regenerates most readily after injury?
A) Endothelium
B) Epithelium
C) Bowman's layer
D) Descemet’s membrane
The corneal epithelium has a high regenerative capacity due to basal
epithelial stem cells.
4. In refractive error, a negative spherical lens is used to correct:
A) Hyperopia
B) Myopia
, C) Astigmatism
D) Presbyopia
Myopia causes light to focus in front of the retina, and negative lenses
diverge light to bring focus onto the retina.
5. Which photoreceptor is responsible for color vision under bright light?
A) Rods
B) Cones
C) Ganglion cells
D) Bipolar cells
Cones mediate photopic (bright light) vision and are sensitive to red,
green, and blue wavelengths.
6. A patient presents with a painful red eye, photophobia, and small
hypopyon. The most likely diagnosis is:
A) Viral conjunctivitis
B) Bacterial keratitis
C) Allergic conjunctivitis
D) Episcleritis
Bacterial keratitis often presents with pain, photophobia, discharge, and
a localized infiltrate with possible hypopyon.
7. Which ocular structure develops from the surface ectoderm?
A) Retina
B) Optic nerve
C) Lens
D) Choroid
The lens originates from the surface ectoderm; the retina and optic nerve
develop from neural ectoderm.
8. The most common form of color vision deficiency is:
A) Blue-yellow
B) Complete achromatopsia
C) Red-green
D) Tritanopia
Red-green deficiencies, including protan and deutan defects, are the
most common inherited color vision defects.
9. Which intraocular pressure-lowering drug works by increasing aqueous
outflow through the uveoscleral pathway?
, A) Timolol
B) Latanoprost
C) Dorzolamide
D) Brimonidine
Prostaglandin analogs like latanoprost increase uveoscleral outflow,
effectively reducing IOP.
10.A patient’s visual field shows a right homonymous hemianopia. The
lesion is likely located in the:
A) Right optic nerve
B) Optic chiasm
C) Left optic tract
D) Left retina
A right homonymous hemianopia indicates loss of the same visual field in
both eyes, typically due to a lesion in the contralateral optic tract.
11.The primary component of the vitreous humor is:
A) Collagen type I
B) Elastin
C) Water
D) Glycosaminoglycan
The vitreous is 98–99% water, with a collagen framework providing
structural support.
12.Which bacteria is most commonly associated with bacterial
conjunctivitis in children?
A) Haemophilus influenzae
B) Pseudomonas aeruginosa
C) Staphylococcus aureus
D) Streptococcus pneumoniae
Haemophilus influenzae is a leading cause of acute bacterial
conjunctivitis in children.
13.The fovea contains:
A) Rods only
B) Cones only
C) Rods and cones
D) Ganglion cells only
The fovea is specialized for high acuity and color vision, containing
densely packed cones without rods.
