“I don’t know the way. Do you?” he asked.

He said that he didn't know the way and did I know it.
He told that he was not knowing the way, but wondered if I knew.
He said that he didn't know the way and asked me if I did.
He asked me if I knew the way which he didn't.

The correct answer is C. He said that he didn’t know the way and asked me if I did.

Option A is incorrect because it does not include the part where the speaker asks the listener if they know the way.

Option B is incorrect because it does not include the part where the speaker says that they do not know the way.

Option D is incorrect because it does not include the part where the speaker says that they do not know the way.

The speaker is asking the listener if they know the way because they do not know the way themselves.