A cloud administrator has received complaints from users about a performance slowdown in a virtualized application. Upon inspection, the administrator noticed that the application's virtual machine is consuming almost all of its allocated memory. After verifying that the application's workload hasn't changed significantly, what should the administrator investigate FIRST as a probable cause for the memory usage issue?
Memory leaks within the application.
Insufficient physical memory on the host system.
Misconfigured cache settings.
Inadequate swap space on the host system.