营运途中若跑掉前轮，应该在速度允许和方向控制的情况下谨慎制动逐渐减速，尽快靠边停车。()

A. scientists are also concerned with the effects of pesticides on animals
B. cancer is the worst effect of the pesticides
C. most or all of the dangerous effects of pesticides are now known
D. the chemicals may also cause these effects in humans

A. seeing is not always believing
B. healthy people also should always go to hospital for a cancer screening
C. through our own physiological system can we eradicate tumors
D. screening for lung cancer, to some extent, may do more harm than good