We cannot leave this tough job to a person ________.
正确答案： B
本题解析：
译文：我们不能把这样一份艰巨的工作交给一个没有自信的人。 本题考查定语从句， have confidence in sb 是固定用法，关系代词 whom用作介词 in 的宾语。
Washing the food down with water as a substitute ________ chewing is not a good habit
He ________ his poor judgment ________ Jet Lag.
Police are ________ the disappearance of two children.
Each of us should _______ aside a few minutes to have a rest every day.
We were told that the stone figure _______ back to the 16th century was of great value.
Perseverance is a kind of quality and that is _______ it takes to do anything well.
You should help them ________ when your friends quarrel with each other.
We are interested in the weather because it _______ us so directly—what we wear, what we do and even how we feel.
—David has made great progress recently. — _______，and _______.