If a young child is obeying a request by their father to put away their toys, and the child is staying on task instead of playing with their toys or finding other distractions, they are showing what capability?

Effortful attention

Explanation:

the ability to inhibit a dominant response and to activate a subdominant response, to plan, and to detect errors. These attention control efforts can also have significant psychological impact on the individuals engaged.

d. i assume the underlined word is "role." reformat if it isn't.

explanation:

role is closest to part because when replacing words, "playing a vital decision," "playing a vital activity," and "playing a vital dollar" don't make logical sense. the only meaningful choice is "playing a vital part."

this fits one of merriam-webster's definitions of role: "a function or part performed especially in a particular operation or process."

the answer to your question is,

d. when a child was born.

-mabel < 3