Answer:
The number 29 is the prime number.
Explanation:
The given numbers are
32,42,29 and 15
Out of these four numbers only 29 is a prime numbers. All the other numbers are composite numbers.
To find factors of other numbers
Factors of 32
1,2,4,8 and 32
Factors of 42
1,2,3,6,7,14,21 and 42
Factors of 15
1,3,5 and 15
Therefore the correct answer is 29