— When could you have a meal with me?

— I'd like to go _______ it is convenient to you.     

A．whichever

B．whenever

C．whatever

D．wherever

下列哪项叙述符合骨髓生理（）

A.黄骨髓具有造血的潜能

B.红骨髓主要有脂肪细胞组成

C.黄骨髓主要由造血细胞组成

D.白骨髓主要为支架细胞

E.分为黄骨髓、红骨髓和白骨髓