Which of the following types of DNA damage cannot be repaired by base excision repair?

a. Depurination

b. Cytosine deamination

c. Thymine dimer

d. Single-strand break

e. Base oxidation

c. Thymine dimer

Explanation:

Thymine dimer

Thymine dimer (also called the DNA damage) that is repaired by the nucleotide excision repair which involves the breakage of the phosphodiester bond on the side of the damage, and results in the excision of an oligolnueotide of 10-12 nucleotides in length.

But the base excision repair involves the removal of the damaged base, removal of short polynuceotide and resynthesis of this area with DNA polymerase.