What is the elevation angle of peak response in the antenna radiation pattern shown in Figure E9-2?

Explication

Only the lowest of the four lobes reaches the outer 0 dB ring, and tracing it puts its maximum at about 8 degrees above the horizon; the higher lobes near 25, 45 and 70 degrees all fall short of the outer ring. Of the values offered, only 7.5 degrees is anywhere near that reading, the rest being several times larger.