It was on the farm ________ he spent his childhood he learned how to grow vegetables．
A.where; thatB.which; whenC.that; thatD.which; which在线课程A
解析：
先行词the farm 在从句he spent his childhood 中作地点状语，故选where；第二空后为强调句的其余部分，应由连词that连接。