Answer:

Explanation:
First digit can be anything from 1 to 5 (5 numbers). What is the probability of getting a "1" in the first digit? It is
.
Second digit can be anything from 2 to 5 (since 1 already in first digit place). What is the probability of getting a "2" in the 2nd digit? It is

Third digit can be anything from 3 to 5 (since 1 and 2 already in first and second digit, respectively). What is the probability of getting a "3" in the 3rd digit? It is
.
The second answer choice is right.