The prime factorization of $1{,}155$ is:

A prime factorization must list **only primes**. Options B and C use composite numbers (77 = 7·11, 33 = 3·11), so they are products of factors but not prime factorizations. Divide successively by primes: $1155 / 3 = 385$, $385 / 5 = 77$, $77 / 7 = 11$, and 11 is prime. So $1155 = 3 \times 5 \times 7 \times 11$. Option D introduces an extra factor of 3, giving $3465 \ne 1155$.