單選題

Yet volunteers do

 (A) _much_ more than that.

 (B) _Some_ volunteers clean up beaches and neighborhoods or take care of stray animals.

 (C) _The others_ run errands for old people

 (D) _living_ by themselves. And

 (E) _still others_ help traffic police or firefighters on the job. There are always opportunities for caring individuals to offer their services.