a$.$The possibility of a deadlock using a resource allocation graph is as follows:C:$\backslash$Users$\backslash$susan$\backslash$Desktop$\backslash 11.$pngExplanation: P$0$ is holding resources A and B$,$ and is waiting for the resource C$.$ P$1$ is holding resources D and E$,$ and is waiting for the resource B$.$ P$2$ is holding resources C and F$,$ and is waiting for the resource D$.$As there is cycle in the resource allocation graph, deadlock occurs.