(B) The best way to enter San Francisco is by crossing the famous Golden Gate Bridge, which offers a fantastic view of the city and the Pacific Ocean—__16__ it’s not too foggy! Once you’re in town, Fisherman’s Wharf is an ideal first stop. In this bay neighborhood, you can try seafood that is as fresh __17__. Stop over at Pier 39 for shopping, and be sure to check out the sea lions relaxing in the sun on the docks.      Afterward, hop aboard one of San Francisco’s famous cable cars, which are the last of their kind still __18__ anywhere in the world. Transfer to the metro and head to the trendy Mission District to see eye-popping wall murals and sip coffee at some of the best cafés in town. Once you’ve had your __19__, take a scenic stroll down the sloping streets of fashionable Nob Hill.
【題組】16
(A) while
(B) since
(C) so that
(D)as long as