I don’t know __.A.what to say or do B.what to say and to do C.how to say and to do

问题描述:

I don’t know __.A.what to say or do B.what to say and to do C.how to say and to do
选谁?为什么

A.
否定句中and变为or.我既不知道该说什么也不知道该做什么.
what to do=how to do it