The key fact is A hypothetical, lossless antenna having equal radiation intensity in all directions used as a reference for antenna gain. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.
Memory hook: A half wave dipole is two quarter wave legs.
The official correct answer for E9A01 is A hypothetical, lossless antenna having equal radiation intensity in all directions used as a reference for antenna gain.
The key fact is A hypothetical, lossless antenna having equal radiation intensity in all directions used as a reference for antenna gain. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.