Lanya prepared 4 different letters to 4 different addresses. For each letter, she prepared one envelope with its correct address. If the 4 letters are to be put into the four envelopes at random, what is the probability that only one letter will be put into the envelope with its correct address?  Choices:	A) 1/24	B) 1/8	C) 1/4	D) 1/3	E) 3/8
Total Lanya# of ways - 4! = 24.   1/3esired:   A-Mapped to the only correct address----------x 1 way only   B-Mapped to other two incorrect addresses - x 2 ways   C-Mapped to other two incorrect addresses - x 2 ways   1/3-Mapped to other two incorrect addresses - x 2 ways   Therefore, 1*2*2*2/24 = 1/3.?
<result>D</result>
Lanya prepared 4 different letters to 4 different addresses. For each letter, she prepared one envelope with its correct address. If the 4 letters are to be put into the four envelopes at random, what is the probability that only one letter will be put into the envelope with its correct address?