--- Life is all about choices. It’s your choice you live a life.
--- I quite agree. It’ you that choose to be in a good mood or bad mood.
A. where
B. why
C. that
D. how
网友回答
A. where
B. why
C. that
(答案→)D. how
解析：考查主语从句：句意：--人生都是关于选择。怎么生活是你的选择。--我很同意，你可以选择情绪差或情绪好。这句话的it是形式主语，后面的从句才是主语，根据句意选how。选D。