Final answer:
The incorrect option is that a multimeter shows no deflection when the probes are reversed on a capacitor in resistance measuring mode. Capacitors behave like open circuits to DC once charged, and probe reversal doesn't change their charged state. Metal wires, LEDs, and resistors will show predictable behaviors, confirming option (d) as the incorrect observation.
Step-by-step explanation:
The question is asking what would be observed when the probes of a multimeter, operating in resistance measuring mode, are reversed while connected across different components. The correct option that would not be observed is:
Multimeter shows no deflection in both cases i.e. before and after reversing the probes if the chosen component is a capacitor.
Here's why the other options can be observed:
For option (d), a capacitor in a DC circuit will behave as an open circuit once it's charged, and reversing the probes won't change this, so no deflection will be observed in both cases with a charged capacitor.
When measuring resistance, an ohmmeter is used and it must be disconnected from any power sources to avoid damaging the meter. If you use a multimeter in the voltmeter mode to measure current, it might lead to a short circuit as voltmeters are designed to have very high resistance. Conversely, using an ammeter mode to measure voltage might mean you are not reading the voltage correctly because ammeters are designed to have very low resistance.
Confirming option (d) as the incorrect observation.