Correct option is A
An antenna array uses multiple elements to combine their individual signals. By carefully controlling the phase and amplitude of the signals fed to each element, the array can focus the total radiated power in a specific direction. This process of constructive interference in the desired direction and destructive interference in other directions results in:
Narrower beamwidth: The angular width of the main radiation lobe decreases, which means the signal is more focused.
Increased directivity/gain: The ability to concentrate energy in a specific direction enhances the directivity and overall gain of the antenna system.
