BECE Mathematics 2025 Paper

Concept:A prime number has exactly two factors, 1 and itself.Solution:Every member $2, 3, 5, 7, 11, 13, 17, 19$ is prime, and these are all the primes less than 20.Not odd numbers: $2$ is even and $1, 9, 15$ are missing. Not factors of 19: those are only $1$ and $19$.Answer:Option C ($M = \{\text{prime numbers less than } 20\}$)