English ? upvoting!

odor pollution is already a problem for those who live near central city dump. people tell me that they can't even stand to be outside for long periods of time. property values in the neighborhood are diminishing. recently, a home sold for two-thirds of the asking price because likely buyers were put off by the smell.
which transition word is best in the blank space?

a. on the other hand
b. however
c. furthermore
d. for instance