In the voltage-loop figure, which pair of elements on the top horizontal branch both have polarity marked $+$ on the left and $-$ on the right? 
A$V_1$ and $V_2$
B$V_3$ and $V_4$
C$V_5$ and $V_6$
D$V_6$ and $V_7$
Answer & Solution
Correct answer: B. $V_3$ and $V_4$
From the figure, the two top branch elements are labeled $V_3$ and $V_4$, and each shows polarity $+$ on the left and $-$ on the right. The other listed pairs are located on different branches or have different orientations.

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