一个细菌或真菌繁殖后形成的肉眼可见的______称为菌落，从菌落的______、______和______可以大致区分细菌和真菌，以及它们的不同种类．

Aunt Mary is crazy about shopping. She must be snapping up the bargains in the department store during such a sale,           ?

A．mustn’t she?

B．isn’t she

C．needn’t she

D．doesn’t she