题目

There was once a group of young people searching everywhere for happiness but what they got was only annoyance, grief and misery. So they   36   Socrates for advice on where happiness   37  . But   38   giving any answers, Socrates asked them to help with building a   39   first. The group of guys had to   40   the task, laying aside their own business of seeking happiness. It took them a long time to cut down a tall tree, gouging out (挖空) the center. Through painstaking effort, they made a canoe out of the tree. They launched the canoe into a river, and then  � 下列哪一个特点与鸟类适应空中生活无关（  ） A、身体呈流线型并覆盖羽毛               B、喜欢吃空中的昆虫 C、有发达的胸肌   D、 骨骼很薄，有的愈合在一起，有的中空