Three of the following statements are comma splices. Choose the one correctly punctuated statement that is not a comma splice.

a) Bike lanes significantly increase the safety of bicyclists, many cities are adding them to their streets.

b) Bike lanes significantly increase the safety of bicyclists, so many cities are adding them to their streets.

c) Bike lanes significantly increase the safety of bicyclists, consequently many cities are adding them to their streets.

d) Bike lanes significantly increase the safety of bicyclists, therefore many cities are adding them to their streets.