As no one knows the truth (as fully as him, no one but him) can provide the testimony:

As no one knows the truth (as fully as him, no one but him) can provide the testimony:

A as fully as his, no one but him

B as fully as he, no one but him

C as fully as he does, not one but he

D as fully as he does, no one but he alone.

Solution

Correct Answer: Option D