The correct answer is:
(b) to determine compatibility of waveform and radio environment
In cognitive radio, the interference objective aims to ensure that the transmission does not cause harmful interference to other users or systems operating within the same spectrum. This involves determining how well a particular waveform (signal) is compatible with the radio environment, which includes factors like the presence of other transmissions, channel conditions, and spectrum availability. By analyzing the interaction between the waveform and the radio environment, cognitive radio systems can adaptively select or modify their transmission parameters to minimize interference and improve spectrum efficiency.