Answer:
She is typically more reserved and passive than her husband.
Explanation:
The excerpt you were given is the following:
Father and son were at chess, the former, who possessed ideas about the game involving radical changes, putting his king into such sharp and unnecessary perils that it even provoked comment from the white-haired old lady knitting placidly by the fire.
....
“Never mind, dear,” said his wife soothingly; “perhaps you’ll win the next one.”
And the possible answers are:
Mr. White lost a game of chess to his son, despite all the unnecessarily risky moves the son made. That frustrates him, but his wife tells him to not mind, that he may have more luck the next time. She is calm and doesn't see what the big deal is, unlike her husband. Her behavior is more passive, more reserved. That's why the correct option is the third one.
The rest of the options are incorrect as she obviously has time for her family (she is spending time with them in the passage), nothing tells us that she is elderly or that she needs care, and her words are not about etiquette or properness but about calming her husband down.
