Imagine That You Are Studying the Control of β-Globin Gene

Imagine that you are studying the control of β-globin gene expression in immature red blood cells (mature red blood cells contain β-globin protein but lack a nucleus and therefore the β-globin gene) .If you deleted a sequence of DNA outside the protein-coding region of the β-globin gene and found that this increased the rate of transcription,the deleted sequence likely functions as a(n) _____.

A) promoter
B) promoter-proximal element
C) enhancer
D) silencer
E) any of the above