During _________ 3-day conference, global warming became _________ major concern of all the representatives.

A．the; a

B．a; the

C．the; \

D．a; \

体育锻炼对肌肉发展的良好影响（）

A.肌肉体积增大

B.肌纤维中线粒体数目增多，体积减小

C.肌肉中脂肪减少

D.肌肉内结缔组织增多