Which sentence below uses transition words?

question 8 options:

a: this law is strictly enforced; to do anything, one must have a special permit, and for every such permit he must pay roundly.

b: it is a well-known fact that many claims on eldorado, hunker, and bonanza creeks have turned out hundreds of thousands of dollars.

c: as to the entire yield of gold from the klondike creeks, none can say except approximately.

d: one half of all mining land is reserved for he crown. however, a quarter or more is gobbled by corrupt officials.