What did you eat for dinner last night?" asked my friend. A. My friend asked me what I ate for dinner the previous night. B. My friend asked me what did I eat for dinner last night.

My friend asked me what I ate for dinner the previous night.

My friend asked me what did I eat for dinner last night.

My friend asked me what I had eaten for dinner the previous night.

My friend asked me what had I eaten for dinner last night.