Please check my understanding, what you're saying is that an emf is produced in the opposite direction in the secondary coil so the net emf in the secondary coil would decrease but from faraday's law this would mean that the rate of change of flux linkage in the secondary decreased(*), which...
This question is given as an exercise in my book. I can't figure out whether this is a poorly worded question or if I misunderstand. The answer I can come up with is that power is dissipated over the load so more power is needed to be supplied by the ac source. This seems too hand-wavy to me...