ABO EXAM AND PRACTICE EXAM NEWEST 2026 TEST
BANK| COMPLETE 650 REAL EXAM QUESTIONS AND
CORRECT DETAILED ANSWERS (VERIFIED ANSWERS)
GRADED A+| ABO EXAM PREP 2026 (BRAND NEW!!)
Q1. How many extra-ocular muscles are inserted into the
sclera to rotate each eye?
a) Four
b) Five
c) Six
d) Eight
Answer: c) Six
Rationale: There are six extra-ocular muscles in each eye: four
rectus muscles (superior, inferior, medial, lateral) and two oblique
muscles (superior and inferior). These muscles work in coordinated
pairs to enable eye movement in all directions.
1
,Q2. Which cranial nerve controls the lateral rectus muscle?
a) Oculomotor (III)
b) Trochlear (IV)
c) Abducens (VI)
d) Optic (II)
Answer: c) Abducens (VI)
Rationale: The lateral rectus muscle abducts the eye and is
innervated by the sixth cranial nerve, the abducens nerve.
Damage to this nerve results in medial deviation of the eye
(esotropia) due to unopposed action of the medial rectus.
Q3. The structure that provides the majority of the eye's
refractive power is:
a) The crystalline lens
b) The cornea
2
,c) The aqueous humor
d) The vitreous humor
Answer: b) The cornea
Rationale: Although the crystalline lens can adjust focus, the
cornea provides approximately two-thirds of the eye's total
refractive power (about 43 diopters). Its curved surface and
refractive index make it the primary refracting surface for light
entering the eye.
Q4. The fibrous tunic is comprised of the:
a) Retina and choroid
b) Sclera and cornea
c) Iris and ciliary body
d) Conjunctiva and sclera
Answer: b) Sclera and cornea
3
, Rationale: The fibrous tunic is the outermost layer of the eye. It is
composed of dense connective tissue and includes the sclera (the
"white" of the eye) and the cornea (the transparent anterior
portion).
Q5. The ability of the eye to bring objects of varying distances
to focus on the retina is known as:
a) Presbyopia
b) Esophoria
c) Accommodation
d) Fusion
Answer: c) Accommodation
Rationale: Accommodation is the process by which the ciliary
muscle contracts, allowing the crystalline lens to become more
convex (increase its refractive power) to focus on near objects.
This ability decreases with age, leading to presbyopia.
4
BANK| COMPLETE 650 REAL EXAM QUESTIONS AND
CORRECT DETAILED ANSWERS (VERIFIED ANSWERS)
GRADED A+| ABO EXAM PREP 2026 (BRAND NEW!!)
Q1. How many extra-ocular muscles are inserted into the
sclera to rotate each eye?
a) Four
b) Five
c) Six
d) Eight
Answer: c) Six
Rationale: There are six extra-ocular muscles in each eye: four
rectus muscles (superior, inferior, medial, lateral) and two oblique
muscles (superior and inferior). These muscles work in coordinated
pairs to enable eye movement in all directions.
1
,Q2. Which cranial nerve controls the lateral rectus muscle?
a) Oculomotor (III)
b) Trochlear (IV)
c) Abducens (VI)
d) Optic (II)
Answer: c) Abducens (VI)
Rationale: The lateral rectus muscle abducts the eye and is
innervated by the sixth cranial nerve, the abducens nerve.
Damage to this nerve results in medial deviation of the eye
(esotropia) due to unopposed action of the medial rectus.
Q3. The structure that provides the majority of the eye's
refractive power is:
a) The crystalline lens
b) The cornea
2
,c) The aqueous humor
d) The vitreous humor
Answer: b) The cornea
Rationale: Although the crystalline lens can adjust focus, the
cornea provides approximately two-thirds of the eye's total
refractive power (about 43 diopters). Its curved surface and
refractive index make it the primary refracting surface for light
entering the eye.
Q4. The fibrous tunic is comprised of the:
a) Retina and choroid
b) Sclera and cornea
c) Iris and ciliary body
d) Conjunctiva and sclera
Answer: b) Sclera and cornea
3
, Rationale: The fibrous tunic is the outermost layer of the eye. It is
composed of dense connective tissue and includes the sclera (the
"white" of the eye) and the cornea (the transparent anterior
portion).
Q5. The ability of the eye to bring objects of varying distances
to focus on the retina is known as:
a) Presbyopia
b) Esophoria
c) Accommodation
d) Fusion
Answer: c) Accommodation
Rationale: Accommodation is the process by which the ciliary
muscle contracts, allowing the crystalline lens to become more
convex (increase its refractive power) to focus on near objects.
This ability decreases with age, leading to presbyopia.
4
