比如这道题：
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.
Awhich was determined by when the sun reached the observer's meridian and differing
Bwhich was determined by when the sun reached the observer's meridian and which differed
Cwhich were determined by when the sun reached the observer's meridian and differing
Ddetermined by when the sun reached the observer's meridian and differed
Edetermined by when the sun reached the observer's meridian and differing
