Composite numbers from 1 to 25: 4, 6, 8, 9, 10, 12, 14, 15, 16, 18, 20, 21, 22, 24, 25 → 15 composite numbers.
$$P(\text{composite}) = \frac{15}{25}$$
Answer: A $\dfrac{15}{25}$
Composite numbers are numbers greater than 1 that are not prime (and not 1). Students often forget that 1 is neither prime nor composite, and may miscount primes (2,3,5,7,11,13,17,19,23 = 9 primes). So composites = 25 − 9 primes − 1 = 15. Option A is correct.