This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Medicine
In molecular cloning, Blue-white screening is used for: 
Select and explain. 
A. To screen for recombinant vectors, B. To detect gene mutations, C. To identify desired chromosomal DNA inse in plasmid vectors, D. To detect host DNA in situ
C: To identify desired chromosomal DNA inse in plasmid vectors
Answer: C: To identify desired chromosomal DNA inse in plasmid vectors 
Explanation: C i.e. To identify desired chromosomal DNA inse in plasmid vectors.