Concept:The phrase "tighten her belt" is an idiom that means to reduce expenses.Explanation:To tighten one's belt means to spend less money and live more frugally.People often tighten a belt when they have less food or money.So after her husband's death, she has to cut down her spending.This does not mean adjusting a physical belt, becoming aggressive, or being greedy.Answer:A. become more economical.