Moderate# Linear Diophantine Equations with Three Variables II

NUMTH-PPPZJS

Let $a, b, c \in \mathbb{Z}$. Then, the equation $ax + by = c$ has infinitely many integral solutions if $\gcd(a, b) | c$ and no solutions if $\gcd(a, b) \nmid c$.

Which of the following linear diophantine equations have infinitely many integral solutions? Select **ALL** that apply.