Several SQL operations are performed by User 1 to access the Fee information for Bowling in the
Act_Fee relation (shown in the exhibit).

The first access returns a fee of 50. An unrelated SQL operation by another user updates the Bowling fee to 60. The second access by User 1 returns a fee of 60. What problem has occurred?

A.
Rollback

B.
Deadlock

C.
Dirty read

D.
No problem has occurred.