Explanation: Solid-state circuit boards, common in RADAR sets and other modern electronic equipment, are highly susceptible to damage from electrostatic discharge (ESD). Even a small, unnoticeable static spark can cause immediate catastrophic failure or latent damage to sensitive components like integrated circuits, transistors, and diodes. Therefore, establishing a proper ESD-safe work environment, including antistatic mats and grounding straps, is essential. This equalizes the electrical potential between the operator and the board, preventing static buildup and discharge. Option B is incorrect because while detaching the waveguide prevents radiation, it's not the primary concern when *handling removed circuit boards* for servicing. Option C is inaccurate; magnetic fields are not used to prevent over-current or overheating in this context. Option D, using non-conductive tools, is important for electrical safety with live circuits but does not address the specific threat of ESD to sensitive components on removed boards; in fact, some non-conductive materials can generate static.