With regards to instrument power cords, what is the required outlet type?

The correct choice is a 3-prong, grounded electrical outlet because it provides a safer and more reliable connection for instruments that require a stable power supply. Grounding is essential as it helps prevent electrical shocks by offering a direct path for any stray electrical current to safely discharge into the ground. This is particularly important in medical or laboratory settings where sensitive equipment is used and where the risk of electrical hazards is more pronounced.

In contrast, a two-prong, ungrounded outlet lacks the grounding feature, which significantly increases the risk of electric shock or equipment malfunction. Extension cord connections are generally not recommended for permanent setups due to potential overloading and increased risk of damage or hazard. Insulated electrical outlets, while necessary for safety, do not specifically refer to the necessity of grounding that is found in a 3-prong outlet. Thus, using a grounded outlet is crucial for both safety and equipment performance.