问题详情

Which of the following occurred as the ices from Halley"s Comet evaporated？
A．Black dust was left on the comet"s surface.
B．The nucleus of the comet expanded.
C．The tail of the comet straightened out.
D．Jets of gas caused the comet to increase its speed.请帮忙给出正确答案和分析，谢谢！