The correct answer is B: The takeoff angle of the lowest elevation lobe decreases. As a horizontally polarized antenna's height above ground increases, the takeoff angle of the lowest elevation lobe decreases. Higher mounting creates lower take-off angles, which are better for long-distance communications. When a horizontal antenna is close to ground, ground reflections create higher elevation lobes. As you raise the antenna, the lowest lobe moves to lower angles. This is because the ground reflection path length changes with height, affecting the phase relationship between direct and reflected waves. Lower take-off angles are desirable for DX work because signals at shallow angles travel farther via ionospheric skip. This is why horizontal antennas are often mounted as high as possible.