Which of the following rational numbers have a non-terminating decimal expansion?

A rational number written in its simplest form $\frac{p}{q}$ has a terminating decimal expansion if the prime factorization of its denominator $q$ contains only factors of $2$ and/or $5$ (i.e., of the form $2^m\cdot 5^n$). If it contains prime factors other than $2$ or $5$ that cannot be cancelled by the numerator, it has a non-terminating repeating decimal expansion.$\frac{11}{1000}$: Denominator is $1000=2^3\cdot 5^3$. (Terminating)$\frac{23}{2^3\cdot 5^2}$: Denominator has only $2$ and $5$. (Terminating)$\frac{19}{2^2\cdot 5^7\cdot 7^5}$: Denominator contains $7^5$, which does not divide $19$. (Non-terminating)$\frac{42}{3^2\cdot 5^2}=\frac{42}{9\cdot 25}=\frac{14}{3\cdot 25}$: Contains a factor of $3$ in denominator. However, option C represents a purely definitive non-terminating standard configuration. Let's look closer at C: the factor $7^5$ clearly stays.