Question

The researchers found clear and convincing evidence _______ happiness is the key when it comes to better health and longer lives.

A．where

B．whether

C．how

D．that

Answer 1

D

考查同位语从句。that解释前面的名词evidence，证据就是快乐是关键当谈到身体更健康寿命更长的时候。所以选D。