单选题 As early as 1647 Ohio made a decision that free, tax-supported schools must be established in every town ______ 50 households or more.

A、 having
B、 to have
C、 to have had
D、 having had

【正确答案】 A

【答案解析】[解析] 本题考查非谓语动词的用法。现在分词短语having 50 households or more做town的定语，因为town和have之间是主动关系。不定式做定语在时间上一般表示将来，所以不能选不定式。句意为：早在1647年，俄亥俄州就做出决定，每个拥有50或50个以上家庭的城镇都应该建立免费的公立学校。