Explain the ramifications to the process of transcription if spliceosomes excise exons and join the remaining introns together

Discuss the three steps of eukaryotic transcription.

Using the transcription unit diagrammed below, in which exons are represented by blue boxes and introns are represented by the connecting lines.  You discover a single base deletion in region E of this DNA sequence. Regarding transcription, this mutation will likely: 1.) Result in an alteration to the mRNA sequence. 2.)Have no effect on transcription or the mRNA sequence 3.)Prevent transcription at the TATAA box 4.) Result in an increase or decrease in the amount of mRNA transcribed

Explain the purpose of splicing the primary transcript and know the name of the ribonucleoprotein complex that carries out this process.Then Diagram and describe generally how splicing occurs.