问白勇语法上的一题

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 determinded by when the sun reached the observer's medridian and differing

B which was determinfed by when the sun reached the observer's merdian and which differed

C which were determinded 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 sun reached the observer's meridian and differing

答案是E. 请问那位达人知道是为什么吗？ 我实在是想不出来了。