The following are true about pupil reaction to light:
a. secretion of acetylcholine is responsible for pupil dilatation
b. constriction of the pupil is mediated by nerve fibres travelling in the short ciliary nerve
c. dilatation of the pupil is mediated by nerve fibres travelling in the long ciliary nerve
d. the sympathetic nerve innervates the dilator muscles

1 Answer

Answer :

the sympathetic nerve innervates the dilator muscles

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