单项选择题A．How Alfred Stieglitz contributed to the history of photography.B．How to analyze photographic techniques.C．How to define photography.D．Whether photography is superior to other art forms.

单项选择题A．The man wants to spend 2 days in San Francisco but the woman disagrees.B．The man wants to spend 2 days in Sequoia and the woman agrees.C．The woman wants to spend more time in San Francisco and the man agrees.D．The woman wants to spend more time in Sequoia but the man disagrees.