GATE Computer Science (CS) 2019 Solved Papers

Consider the following snapshot of a system running $\mathit{n}$ concurrent processes. Process $\mathit{i}$ is holding $\mathit{X}\mathit{i}$ instances of a resource $\mathit{R},1\le \mathit{i}\le \mathit{n}.$ Assume that all instances of $\mathit{R}$ are currently in use. Further, for all $\mathit{i}$, process $\mathit{i}$ can place a request for at most $\mathit{Y}\mathit{i}$ additional instances of R while holding the $\mathit{X}\mathit{i}$ instances it already has. Of the $\mathit{n}$ processes, there are exactly two processes $\mathit{p}$ and $\mathit{q}$ such that $\mathit{Y}\mathit{p}=\mathit{Y}\mathit{q}=$ 0. Which one of the following conditions guarantees that no other process apart from $\mathit{p}$ and $\mathit{q}$ can complete execution?