A long line with a camera ------to it was put into the dolph

A long line was put into the dolphin's stomach to find out where the plastic ball was.
with a camera attached to it 修饰a long line
it ate 修饰 the plastic ball
绑在相机上的长线被放进海豚的胃中,为了发现它吃下的塑料球的位置
所以选A