This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Transcription, Subject name: Biochemistry
snRNA which is not the pa of spliceosome: 
Select and explain. 
A. U1, B. U2, C. U3, D. U4
C: U3
Answer: C: U3 
Explanation: snRNA- small nuclear RNA - U1, U2, U4, U5 and U6 are involved. They remove introns by forming base pairs with the consensus sequences at each end of the intron.