Concept:The word "reprimand" means to scold or criticize sharply. Its opposite should express praise or approval.
Explanation:The sentence contrasts two ways of treating children.
If you should not always "reprimand" them, then at other times you should do something positive.
"Scold" and "criticise" are negative actions.
The correct opposite here is to "compliment", which means to praise or admire.
The sentence then reads: "Do not always reprimand your children; it is good to compliment them at times."
This makes logical sense because praising children sometimes is the opposite of always scolding them.
Answer:C. compliment