Question

---How much _______ the shirt?

---_______ thirty yuan.

1. A.
   is; It's
2. B.
   are; They're
3. C.
   is; They're
4. D.
   are; It's

Answer 1

A
问句中主语the shirt为第三人称单数形式，故第一空应填is，那么答语的主语自然也应用表示单数的It's来指代。