提问一题

老螃蟹

11.    The growth of the railroads led to the abolition of local times, which was determined by when the sun reached the observer’s meridian and differing from city to city, and to the establishment of regional times.
(A) which was determined by when the sun reached the observer’s meridian and differing
(B) which was determined by when the sun reached the observer’s meridian and which differed
(C) which were determined by when the sun reached the observer’s meridian and differing
(D) determined by when the sun reached the observer’s meridian and differed
(E) determined by when the sun reached the observer’s meridian and differing
想不明白c为啥不对，c中which指代localtime不行吗？

xiang_y

which可以指代localtime， 但differing 和 which 从句不平行。即使把differing 当作和determined 共用were也不能解释为什么要用过去进行时。