There are no options given in respect to the question and so it is not possible to choose. I would answer this question based on my knowledge and hope it satisfies you. he form of radio active decay that would be most likely detected by you if it were happening in the room next to the one you are currently standing in is gamma.
When primary coil is exited by sin wave,this will result in sin wave in secondary coil as well.According to law,flux induced in the secondary coil will have same waveform as in the primary coil.