Answer: The correct answer is-
B. GCA TAT.
DNA replication is a process of formation of two molecules of DNA using single molecule of DNA ( which is double stranded).
In this process, two strands are first separated and act like template strand, using which enzyme DNA polymerase adds dNTPs ( deoxyribonucleoside triphosphate) in the direction 5' to 3'.
According to Watson and Crick base pairing, Adenine in the DNA pairs with Thymine and Guanine pairs with Cytosine during the process of replication of DNA.
As per the information, given strand of DNA is - CGT ATA
Thus, the sequence of compementary strand would be- GCA TAT