During Middle Age,the Visual System Begins to Change

question 9

Multiple Choice

During middle age,the visual system begins to change.Which of the following is NOT one of those changes?

• A)Accommodation ability of the eye diminishes.
• B)The size of the retinal blind spot diminishes.
• C)More illumination is required for visual work.
• D)It is necessary to have glasses that focus on multiple distances.

---

Definitions:

(2R,4S)-4-propylhexane-2-thiol

A chiral molecule specified by its configuration, comprising a six-carbon chain with a propyl group and a thiol group at specific positions.

(2S,4R)-4-ethylheptane-2-thiol

A chiral organic compound characterized by a specific three-dimensional configuration, including an ethyl and a thiol group on a heptane backbone.

(2R,4S)-4-ethylheptane-2-thiol

A specific stereoisomer of a compound featuring an ethyl group and a thiol group attached to a heptane chain.

(R)-3-methylpent-1-ene

A specific optical isomer of an organic compound with a branched five-carbon chain, featuring a double bond at the first carbon and a methyl group at the third position.