Final answer:
When the common-ground reference point is connected to the negative terminal of a source voltage, all voltages in the circuit with respect to ground are positive. Therefore, the correct answer is c) Zero.
Step-by-step explanation:
When the common-ground reference point is connected to the negative terminal of a source voltage, all voltages in the circuit with respect to ground are generally considered positive. This is because ground potential is often taken to be zero (Vground = 0), and by convention, the potential difference measured with respect to ground is positive if it is higher than the ground potential.
In the case of the negative terminal being connected to ground, since every other point in the circuit will have a higher potential than the ground reference, the measured voltages will be positive.
If the common-ground reference point is connected to the negative terminal of the source voltage, all voltages in the circuit with respect to ground are zero.
This is because the ground potential is often taken to be zero. The voltages in the circuit are measured by comparing them to the ground potential. Therefore, if the common-ground reference point is connected to the negative terminal, all voltages in the circuit will be zero.