— Must I go to the gym three times a week?

— No, you _____. Twice a week is OK. [ ]

A. mustn't

B. needn't

C. can't

D. shouldn't

塔式中高层住宅每层建筑面积为( )。

A．不超过500m²

B．不超过600m²

C．不超过800m²

D．不超过1000m²