Which Is an Example of Regulation of Eukaryotic Transcription

Multiple Choice

Which is an example of regulation of eukaryotic transcription?

A) Iron binding the repressor protein for the ferritin mRNA and increasing ferritin expression
B) Proteasome breakdown of protein-polyubiquitin complexes
C) MicroRNAs binding their target mRNA and causing its degradation
D) Alternative splicing of an mRNA transcript
E) Activator proteins binding an enhancer