Some researchers are finding that daydreaming may be important to ________ mental health. Daydreaming，they say，is ________ good means of relaxation.

       A.the; /                  B．/; the         C．/；/       D．/; a

 .Some  researchers are finding that daydreaming may be important to 　　　　 mental health. Daydreaming， they say， is 　　　　 good means of relaxation.

A. the；不填　   B. 不填； the      C. 不填；不填        D.不填； a