题目

用方框内所给词的适当形式完成下面短文 it placewithout carry through In some parts of the world there are large deserts. There aren't trees or water in these Travellers must take food and water with them. The only animal that can walk the desert is the camel. It can go food or water for a long time, and it can heavy things. People call the camel “the ship of the desert”. The camel is very big. It has one or two humps on back, short ears and a long neck. The camel can hold water in twelve deep pockets. Each pocket has a mouth, and the food doesn't mix with 已知函数f（x）=x2-，则函数y=f（x）的大至图象是（ ）A．B．C．D．