How is splicing regulated at the level of cis-acting RNA sequence elements?

• A. Splicing repressors bind splicing silencers and decrease nearby splice junction activity. Splicing activators bind splicing enhancers and increase likelihood of proximal sites as splice junction.
• B. Splicing repressors bind splicing silencers and decrease nearby splice junction activity. Splicing activators bind splicing promoters and increase likelihood of proximal sites as splice junction.
• C. Splicing repressors bind splicing silencers and increase nearby splice junction activity. Splicing activators bind splicing enhancers and decrease likelihood of proximal sites as splice junction.
• D. Heterochromatin prevents alternative splicing whereas euchromatin promotes alternative splicing