Question

when measuring resistance with an ohmmeter, a observe polarity. b disconnect power. c add power. d insulate probes.

Explanation:

When using an ohmmeter to measure resistance, power must be disconnected from the circuit being measured. This is to prevent damage to the ohmmeter and to get an accurate resistance - value reading. Resistance is a property of a component or circuit in the absence of an external power - source driving current through it. Polarity is not relevant for most resistance measurements (resistors are usually non - polar). Adding power would interfere with the measurement, and insulating the probes is not a necessary step for basic resistance measurement.

Answer:

B. disconnect power