Question

All that can be eaten _______ eaten up

1. A.
   are being
2. B.
   has been
3. C.
   had been
4. D.
   have been

Answer 1

B
本句话中，主句的主语是all,为抽象概念。因此，其谓语应用单数的has been。关系代词that引导定语从句，并在从句中作主语。