What have the television brought to the lives of the old, the sick, and the lonely
The （）.

A．They combined vocal sounds with hand or body signals to express messages.
B．Some words may be similar to natural sounds.
C．Others may have come from expressions of emotion, such as laughter or crying.
D．The language, some theorists believe, is a result of individual activities, such as working together or dancing.

A．the blood type of the donor was not compatible with that of the recipient
B．the blood type of the recipient was not suitable for that of the donor
C．blood type A contains red blood cells that have a substance A on their surface
D．blood cells are necessary for blood transfusion