---Where were you this morning?-I in the supermarket.A. will shopB. am shoppingC. was

问题补充：

---Where were you this morning?

---I in the supermarket.

A. will shop

B. am shopping

C. was shopping

D. have shopped

答案：

A. will shop

B. am shopping

C. was shopping

D. have shopped

解析：考查动词的时态。根据句意，问句中用了were，应该用过去时来回答。was shopping是过去进行时，符合句意。故选C。