"Ask me if I'm surprised to hear that."

Spoilers: he's not. Starscream is audacious enough to do that. Bumblebee doesn't know about this 'chosen one' stuff spewed out by the titan - if it's true or not, that is. He isn't sure if Starscream actually believes that either or is just using it. Him wearing a crown? Yeah, the jet is tacky like that.

"It's not desperation either though, Rodimus. Just... Give the guy a chance, all right? That's all."