Four red balls, four green balls and four blue balls are put in a box. Three balls are pulled out of

Q. Four red balls, four green balls and four blue balls are put in a box. Three balls are pulled out of the box at random one after another without replacement. The probability that all the three balls are red is

(A) 1/72                      (B) 1/55                      (C)  1/36                     (D) 1/27

Ans: 1/55