5 cards have to be put into their 5 respective envelopes. If the letters are inserted randomly into the envelopes, what is the probability that all the cards go into their respective envelopes?  Select the correct option:
A) 1/30
B) 1/60
C) 1/240
D) 1/120
E) 3/5
A-B-C-D-E (envelopes)   a-b-c-d-e (letters)   5 letters (a, b, c, d, and e) can be assigned to 5 envelopes (arranged) in 5! ways, out of which only one will be correct, thus the probability is 1/5! = 1/120.   Answer: 1/120.
<result>D</result>
5 cards have to be put into their 5 respective envelopes. If the letters are inserted randomly into the envelopes, what is the probability that all the cards go into their respective envelopes?