we can not figure out quit a number of insects birds and animals are dying out .A. thatB

问题补充：

we can not figure out quit a number of insects ,birds ,and animals are dying out .

A. that

B. as

C. why

D. when

答案：

A. that

B. as

C. why

D. when

解析：figure out后接宾语从句，根据从句要表达的意思“为什么很多昆虫，鸟，和动物在逐渐灭绝”