In Lead II, which site is negative and which is positive?

• A. Left foot positive; Right shoulder negative
• B. Right shoulder negative; Left foot positive
• C. Left shoulder negative; Right foot positive
• D. Right arm negative; Left leg positive

Answer: (B)

In Lead II, the measurement is taken between the right arm and the left leg. The negative electrode sits on the right arm (often described as the right shoulder area) and the positive electrode sits on the left leg (often described as the left foot). So the correct pairing is right arm/shoulder as negative and left leg/foot as positive. This matches the option that states the negative site on the right shoulder and the positive site on the left foot. The lead’s orientation is all about which limb hosts the negative electrode and which hosts the positive, with Lead II specifically defined as RA negative and LL positive.