The author says it is ______ that teachers be sympathetic with their students.

A．The personnel manager should be fired for inefficiency.
B．A few engineers should be employed to modernize the factory.
C．The entire staff should be retrained.
D．Better-educated employees should be promoted.

A．Turning right at a red light.
B．Driving in freeways without a local driver’s license.
C．Passing a school bus that is letting off children.
D．All of the above.