Which transcription factors are normally bound to the Psf promoter in the presence of both Mg2+ and Ca2+? 10:56 Biology Which transcription factors are normally bound to the Psf promoter in the presence of both Mg2+ and Ca2+? (a) MetA and MetB (b) MetB and MetC (c) MetA and MetC (d) MetA, MetB, and MetC Answer: C Learn More : Share this Share on FacebookTweet on TwitterPlus on Google+