3 V
16 V
7.5 V
8 V E. None of the above
Answer is Wrong!
Answer is Right!
The correct answer is $\boxed{\text{D}}$.
When two voltage sources are connected
in series-opposing form, the total voltage is the difference between the two source voltages. In this case, the total voltage is $9 \text{ V} – 6 \text{ V} = 3 \text{ V}$.Option A is incorrect because it is the sum of the two source voltages. Option B is incorrect because it is twice the sum of the two source voltages. Option C is incorrect because it is the average of the two source voltages. Option E is incorrect because it is not a possible value for the total source voltage.