单选题 What we consider a luxury at one time frequently becomes a ______, many families find that ownership of two cars is indispensable.
【正确答案】 B
【答案解析】(necessity必需品)。句意为：我们曾经认为是奢侈品的东西往往会成为必需品，如今许多家庭觉得必须拥有两辆小汽车。A．fad时尚；C．trend趋势；D．nuisance讨厌的东西。