SASMO 2018 Secondary 1 (Grade 7) Contest Question 4

Question 4

If p is a prime number, then which of the following is NOT ALWAYS true?

1. The number 2 x p is an even number.
2. The number 2 x p + 3 is an odd number.
3. The number p x p is not a prime number.
4. The number 3 x p + p is not a prime number.
5. The number p + 1 is an even number.