– Are you still thinking about yesterday’s football match against Class 25?

-- Oh, that’s _________.

A．what makes me feel upset

B．whatever I feel upset about

C．how I feel upset about it

D．when I feel upset

内毒素的主要成分是（）

A.磷脂

B.脂多糖

C.蛋白质

D.胶原

E.无机盐类