ANSWER

Step-by-step explanation
We want to find the probability that the student selects the correct answer on all questions.
For each question, there is only 1 possible correct answer out of 5 options. This means that for each question, the probability of selecting the correct answer is:

Therefore, for 5 questions (with 5 options each), the probability of selecting the right answer will be the product of selecting the right answer for each of the 5 questions.
That is:

That is the answer.