题目选项分析

A compelling optical illusion called the illusion of velocity and size makes objects appear to be moving more slowly the larger the objects are.Therefore, a motorist's estimate of the time available for crossing a highway with a small car approaching is bound to be lower than It would be with a large truck approaching.The conclusion above would be more properly drawn if it were made clear that the .

【选项】truck's speed is assumed to be higher than the car's