My mother is very busy. She has ____ time to help me with my lessons.

Few.   A few.     Little.     A little.  

C

Little.   形容词：较小的，微小的，几乎没有（否定意义）与不可数名词连用

Few.   从容词：不多，很少都是（否定意义）与可数名词连用

 The price of the guitar ____ too high for his to buy.

Has been risen.   Has risen.  Has been raised.    Has raised

第二个B