A．other old menB．other senatorsC．other politiciansD．any……

单项选择题Mugging are most likely to occur ______.

单项选择题The experiments in giving the virus to animals proved that this type of influenza was easy to catch ______.

单项选择题It doesn't happen very often, but it does happen in the capital city of the United States. It refers to ______.

单项选择题The youths probably shot Senator Stennis because ______.

单项选择题One reason why the outbreak of the disease was not discovered sooner was that ______.