问题
选择题
________ the calculation is right, scientists can never be sure that they have included all variables and modeled them accurately.
A．Even if
B．As far as
C．If only
D．So long as
答案
答案：A
A 考察，从。Even if即使，纵然；引导让步状语从句。句义：即使计算结果正确，科学家也无法肯定他们已经把所有的变量都包括进去并进行了准确的模拟。根据句义说明A正确。