Which of the following is a valid inference of $\mathrm{X, Y}$ in first-order logic? $$ \begin{aligned} & \text{X}: \forall x .(\mathrm{P}(x) \rightarrow \mathrm{Q}(x)) \\ & \text {Y}: \forall x .(\neg \mathrm{R}(x) \rightarrow \neg \mathrm{Q}(x)) \end{aligned} $$
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