E9C02 — Amateur Extra Class

E9C02 : What type of radiation pattern is created by two 1/4-wavelength vertical antennas spaced 1/4-wavelength apart and fed 90 degrees out of phase?
A Cardioid
B A figure-eight end-fire along the axis of the array
C A figure-eight broadside to the axis of the array
D Omni-directional
Correct Answer: Cardioid