Final answer:
The gene that is NOT an example of a Mutator gene is B. DnaQ-Polymerase III epsilon subunit, as it's part of the DNA polymerase III holoenzyme and not involved in increasing mutation rates.
Step-by-step explanation:
The student's question asks which gene is NOT an example of a Mutator gene. Mutator genes are those that increase the spontaneous mutation rate in an organism. They might be involved in DNA repair, replication, or the regulation of these processes. In the choices provided, DnaQ-Polymerase III epsilon subunit (B) is not a Mutator gene; rather, it's part of the DNA polymerase III holoenzyme involved in DNA synthesis and proofreading to ensure the accuracy of DNA replication.
Mutator genes like MutH, MutS, and MutL (A) are part of the mismatch repair system in bacteria. FEN1 endonuclease (C) is involved in DNA repair and replication, playing a role in Okazaki fragment maturation and lagging-strand synthesis. UvrD (D) is a helicase that is involved in nucleotide excision repair processes. Therefore, the correct answer is B. DnaQ-Polymerase III epsilon subunit, which is critical for DNA synthesis and reliability rather than being a mutator gene.