Which roll number has only prime digits?
Show answer & explanation
Correct answer: B
Explanation
The correct answer is option 2 i.e. 357.
Prime digits are 2, 3, 5, and 7.
- 239 → 9 is not prime
- 357 → 3, 5, and 7 are all prime
- 468 → 4, 6, and 8 are not prime
- 579 → 9 is not prime