Answer:
A.
The number 42 is a composite number. Now let us find the prime factors of 42.
The first step is to divide the number 42 with the smallest prime factor, i.e. 2.
42 ÷ 2 = 21
Now, check whether 21 can be further divided by 2 or not.
21 ÷ 2 = 10.5
But, a factor cannot be a fraction. Therefore, we will proceed to the next prime number, which is 3.
Now, dividing 21 by 3 we get,
21 ÷ 3 = 7
Again, dividing 7 by 3 will give a fraction number. Therefore, taking the next prime number, 5, into consideration.
21 ÷ 5 = 4.2, again a fraction number.
So the next prime number is 7.
7 ÷ 7 = 1
We have received 1 at the end and further, we cannot proceed with the division method, as we know the multiple of 1 is 1 only. So, the prime factors of 42 are 2 × 3 × 7, where 2, 3 and 7 are prime numbers.
