.-----I heard that many westerners prefer vegetables to meat.

-----It is true. Americans eat ___ vegetables each person today as they did 20 years ago.

A．more than twice

B．as twice as many

C．twice as many

D．that twice as many

装备活塞发动机的飞机在飞行中发现气缸头温度表失效，可通过参考什么仪表间接判断发动机的温度（）？

A.进气压力表和转速表；

B.滑油温度表和排气温度表；

C.燃油流量表和燃油压力表。