问题如下图：
选项：
A. 
B. 
C. 
D. 
解释：
Why not B? Delta-normal is not appropriate for estimating VaR on options, and zero-drift of course will underestimate VaR as well. I know historical simulation will underestimate VaR too based on inflated market, but I was wondering why B is still "better" than D.
