The Primary Difference Between an Enhancer and a Promoter-Proximal Element

The primary difference between an enhancer and a promoter-proximal element is that:

A) Enhancers are transcription factors; promoter-proximal elements are DNA sequences.
B) Enhancers enhance transcription; promoter proximal-elements inhibit transcription.
C) Enhancers are part of the core promoter; promoter-proximal elements are regulatory sequences distinct from the core promoter.
D) Enhancers are at considerable distances from the core promoter; promoter-proximal elements are close to the core promoter.