Most substances contract when they freeze so that the density of substance's solid is （） of its liquid.

单项选择题The basic theory of government rests on the assumption that men have naturally （） interests.

A．competitive
B．conflicting
C．contentions
D．combative

单项选择题Because we had eaten turkey on Thanksgiving for so many years, we never wondered whether some other dish might be an equally tasty （）.

A．alternative
B．altercation
C．alteration
D．allusion