Research has found that parents in mid-life who have experienced the death of a child in war or in a traffic accident may experience anxiety, relationship difficulties, and problems in functioning for as long as years.

option c

explanation:

strive for superiority

productive most commonly means: achieving or producing a significant amount or result.

explanation:

productive can also mean:

these depend on how the word productive is used. most likely productive will mean   achieving or producing a significant amount or result.