According to the passage, policemen spend most of their time and efforts______.

A．Because they do not receive due support from society.
B．Because they find people insincere with them.
C．Because they feel superior to simple-minded people around them.
D．Because they are suspicious of the people around them.

A．He has to get the most desirable results without breaking the law in any way.
B．He has to justify his arrests while unable to provide sufficient evidence in most cases.
C．He can hardly find enough time to learn criminal law while burdened with numerous criminal cases.
D．He has to provide the best possible public service at the least possible expense.