The best answer is A. Liquid cooling. A system designed for sustained high CPU utilization and heavy graphics usage needs strong thermal management. The study guide explains that the CPU is one of the greatest cooling challenges in a computer and that modern processors require active cooling. It also notes that high-performance CPU coolers use large heat sinks, high-CFM fans, and better heat transfer methods to dissipate processor heat. Liquid cooling is specifically listed as a CPU cooling method and is described as using a water block to conduct heat away from the processor and circulate it to a radiator for cooling. The Mike Meyers material also explains that liquid cooling is useful for systems that are overclocked or need quieter, stronger cooling. Advanced RISC and x86 describe CPU architecture, not a cooling improvement. A hardware security module protects cryptographic keys and does not help with CPU/GPU heat or performance stability.
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