下列各项中，没有语病的一项是(　　)

Smokers are more __________ to have a heart attack than nonsmokers.

_________to nuclear radiation, even for a short time, may produce variants of genes in human bodies.

I think my father is a hero. He is not only strict ________ us but also strict ________ his work.

s the long March Rocket 2F, as reported, sent Shenzhou VI spaceship into space.