单选题 The earliest controversies (about) the relationship between photography and art centered on (if) photography"s fidelity (to) appearances and dependence on a machine allowed it to be (a) fine art.
【正确答案】 B
【答案解析】[解析] if改为whether。这里考查if与whether的区别，两者都表示“是否”，介词后只能用whether，句中有介词on，因此应用whether。