Long before America’s mass preoccupation with Bill Clinton’s crotch area, one high school student had the nerve to ask about it on national television. “Mr. President, all the world’s dying to know,” said Laetitia Thompson, 17, of Potomac Md., at an MTV-sponsored forum of 200 young people in April 1994. “Is it boxers or briefs?” When the laughter died down, Clinton didn’t duck the question: “Usually briefs,” he said. “I can’t believe she did that.”