Question

Assertion (A): A piece of DNA inserted into an alien organism generally does not replicate, if not inserted into a chromosome. Reason (R): Chromosomes have specific sequences called 'ori' region, where DNA replication is initiated.

Suneeta is planning an experiment to clone a gene in a vector. So, she has to choose a good cloning vector. Which one of the vectors shown below should she choose? Justify your answer by giving two reasons.