Final answer:
DNA repair systems that involve the removal of a segment of a DNA strand include base excision repair, nucleotide excision repair, and mismatch repair; all are correct and therefore, the answer is D, All of the above.
Step-by-step explanation:
The DNA repair systems that involve the removal of a segment of a DNA strand are base excision repair (BER), nucleotide excision repair (NER), and mismatch repair. In BER, DNA glycosylases remove damaged bases and the site is then repaired. NER is used to remove bulky, helix-distorting lesions such as thymine dimers or larger-scale damage on strands of 2-30 bases; segments of DNA are cut out on both the 3' and 5' ends of the lesion and replaced with correct nucleotides. Mismatch repair fixes mistakes post-replication by removing the incorrect base and replacing it with the correct base after DNA synthesis errors are detected. Thus, the correct answer is D, All of the above, as each of these pathways can entail cutting out segments of DNA to maintain genomic integrity.