I didn't watch either, but HuffPo had a story:

Former New Jersey Gov. Chris Christie was baffled when he was singled out to answer “the UFO question” at Wednesday night’s GOP primary debate.

“C’mon, man!” Christie said, chuckling, after co-moderator Martha MacCallum began her query about the “recent spike in UFO encounters.”

“I get the UFO question?” he added, to loud laughter from the audience.

“If you were president,” MacCallum continued, “would you level with the American people about what the government knows about these encounters?”

Christie joked that it was “horrible” that the Fox News host, a fellow New Jersey native, asked him “about unidentified flying objects and Martians” just because he’s from the state.

“We’re different, but we’re not that different,” he quipped.

Jokes aside, Christie said the president’s job is to be honest with the public, whether discussing UFOs or issues with the education system.

“Look, the job of the president of the United States is to level with the American people about everything. The job of the president of the United States is to stand for truth,” he said.