A bag contains 4 white marbles and 4 black marbles. If each of 4 girls and 4 boys randomly selects and keeps a marble, what is the probability that all of the girls select the same colored marble?	Choose the most appropriate option
A) 1 / 35	B) 1 / 9	C) 1 / 10	D) 1 / 20	E) 1 / 30

Rationale: "first , total ways to select for all boys and girls , i . e 8 ! / ( 4 ! * 4 ! ) = 8 * 7 * 6 * 5 * 4 * 3 * 2 * 1 / 4 * 3 * 2 * 1 * 4 * 3 * 2 * 1 = 70 then there are one two way girls can have all same colors , either white or black . the number of ways in which 4 girls can select 4 white balls = 4 c 4 = 1 the number of ways in which 4 girls can select 4 black balls = 4 c 4 = 1 therefore , total favorable outcomes / total outcomes = 2 / 70 = 1 / 35 a"
Answer: A