Final answer:
For treating cockroaches inside computers, baits and traps are the safest and most effective method as they do not risk damaging sensitive computer components.
Step-by-step explanation:
Treatment of cockroaches inside of computers is a complex issue due to the sensitive electronic components that can be damaged by many traditional pest control methods. Among the options listed, Baits/traps should be used as they are non-invasive and don’t pose a risk to the computer hardware. Heat treatments, whether with steam or combined with sanitation, could damage the computer components, and applying liquid residuals is risky for the same reason. Baits and traps offer a safer alternative that can effectively reduce cockroach populations without harming the computer.