Question

Chemists find _____ to detect and measure the amount of chlorine in any given water supply.

1. A.
   are easy
2. B.
   easily
3. C.
   it easy
4. D.
   how easily

Answer 1

C
解析：
后面的the amount of chlorine in any given water supply.雖然并不重要，但其過去分詞given的用法和supply作為名詞的使用以及名詞water作為定語的使用特點，都值得注意。