Giải thích giúp em luôn ạ

1.Peter works for a factory ______ makes motorbikes.

A.what​​B. which​​C. who​​D. whom

2.What’s the name of the gril______ bicyclewas stolen?

A.whose​​B. who​​C. which​​D. that

3.The children,______parents work late, are taken home by bus.

A.that​​B. whom​​C. whose​​D.their

4. I took the damaged wacth to my wacth maker_____knows how to repair all sorts of things.

A.who​​B.whom​​C. whose​​D.which

5. I don’t like stories_____ have an unhappy ending.

A. whose​​B. whom​​C. who ​​D. that

6. We’ll talk about those_____ problems are related to psychology.

A.what​​B. which​​C. whose​​D.who

7.The man_____ we met yesterday was the manager of a bicycle factory.

A.when​​B. whose​​C. who​​D. which

8.Most folk songs are ballads_____ have simple words and tell simple stories.

A.what​​B. who​​C. whose​​D. that

9.The kind of music_____ their group plays is hard to understand.

A.that​​ B. what​​C. who​​D. whose

10.She is the writer_____ books I always like to read.

A.that​​ B. which​​C. whom​​D.whose