Choose the correct description, of how would we be able to tell, if fusion reactions in the Sun were to suddenly cease. Choose the correct description, of how would we be able to tell, if fusion reactions in the Sun were to suddenly cease. We would be able to tell that fusion reactions had ceased because we would no longer detect electrons from the Sun. Electrons, a main product of nuclear fusion, exit the Sun immediately. We would be able to tell that fusion reactions had ceased because we would no longer detect electrons from the Sun. Electrons, a by-product of nuclear fusion, exit the Sun immediately. We would be able to tell that fusion reactions had ceased because we would no longer detect neutrinos from the Sun. Neutrinos, a by-product of nuclear fusion, exit the Sun immediately. We would not be able to tell that fusion reactions had ceased because light and particles generated by fusion take hundreds of thousands years to exit the Sun.