Although the United States cherishes the tradition that it is a nation of small towns and wide open spaces, only one in eight Americans now lives on a farm.

A．cheers for

B．tends lovingly

C．misses

D．remembers

检查发动机点火波形发现其点火线均偏低，造成此现象的最大可能原因是（）。

A.分火头与分火盖触点间的间隙过大

B.高压点火线电阻达23KΩ

C.火花塞间隙均偏大

D.火花塞积炭较多