Peridot is about to politely point out-- meaning, shout at him in a way that is not actually polite at all-- that Strange is the one that needed four whole strokes to get through this hole when she's about to get it in just three, so if anyone is holding the other group up, it's HIM... And then the comment happens.

This one succeeds in rubbing her the wrong way, because it more directly implies that she's some kind of human juvenile, which she absolutely is NOT? She whirls on the muttering guy, already seething, and points an accusatory claw in his direction. "I am NOT a KID!!!" she snarls, puffing up indignantly. "I am a-- Uh---"

Crap. She falters. What the heck's a normal human age for her cover?

"...I have survived FIFTY FIVE rotations of this planet around the Earth's sun, and I don't plan on stopping any time soon!"

Nailed it.