Final answer:
The C) lagging strand is more likely to have mutations due to the discontinuous nature of its synthesis and the necessity for DNA Ligase to seal the Okazaki fragments. This makes the lagging strand prone to errors if there's an issue with the DNA Ligase's action. Thus, the answer is (C) Lagging Strand.
Step-by-step explanation:
The question is asking which part of a DNA strand is most likely to carry mutations due to DNA Ligase's lack of proofreading capabilities. DNA Ligase is an enzyme that seals nicks between Okazaki fragments on the lagging strand during DNA replication. The lagging strand is synthesized in short segments known as Okazaki fragments that require DNA Ligase to join them together, while the leading strand is synthesized continuously. Although both strands may incur errors during replication, the discontinuous nature of the lagging strand synthesis and the action of DNA Ligase in sealing the Okazaki fragments make the lagging strand more likely to have mutations if there is a problem with the action of the DNA Ligase. The primase enzyme synthesizes a short RNA primer on the lagging strand for each Okazaki fragment. This strand is synthesized in the 5' → 3' direction but away from the replication fork as compared to the leading strand which moves towards the replication fork. Once the RNA primers are removed and replaced with DNA, DNA Ligase then seals the gaps, forming the necessary phosphodiester bonds. Considering the multiple steps and enzymes involved in the synthesis of the lagging strand, including the crucial role of DNA Ligase, the lagging strand is most likely to have mutations if a cell strain shows impaired joining of Okazaki fragments. Therefore, the correct answer is (C) Lagging Strand.