The correct answer is C because Live Migration allows you to move your instance to a machine type with higher memory with minimal to no downtime. This feature is designed to keep your virtual machine instances running during various host system events, including maintenance and upgrades, without requiring a reboot. Options A and B are incorrect as you cannot directly increase the memory of an instance via the console or command line. Option D is also incorrect because the issue is related to memory, not CPU, so migrating to a machine type with a higher CPU count would not address the memory problems.