—Nowadays the doctors are trying their best to reduce the people’s fear they would be affected by the present disease called “Bird Flu （禽流感）”.
A. whether
B. which
C. that
D. when
网友回答
A. whether
B. which
(答案→)C. that
D. when
解析：fear后为同位语从句。在同位语从句、表语从句、主语从句中的引导词that一般不省略。故选C。