It's a better answer than it could have been. At least he can be sure that, with Megatron showing uncertainty, it's very unlikely that he is being dishonest. If Megatron is still anything like he was on Cybertron, that wasn't a weakness in conviction he would make up.

"That's understandable, to say the least," he says, feeling himself becoming more reserved in response to his own emotional stress, not wanting to allow the chance of saying something ridiculous. "More importantly, I think, is the question of whether that is something you...still have any desire of finding out."

He glances up at him, solemnly.

"You were...are...one of my dearest friends. And I only wish to make things right."