问题如下：
The following table shows the annual returns for Fund Y.
The geometric mean for Fund Y is closest to:
选项：
A. 14.9%.
B. 15.6%.
C. 19.5%.
解释：
A is correct.
The geometric mean return for Fund Y is found as follows: Fund Y = [(1 + 0.195) × (1 – 0.019) × (1 + 0.197) × (1 + 0.350) × (1 + 0.057)](1/5) – 1 = 14.9%.
括号里为什么都加一呢