Assertion : DNA polymerase -I acts as proofreader.
Reason : DNA polymerase-I removes mismatched nucleotides.

Options

A. If both the assertion and the reason are true and the reason is a correct explanation of the assertion
B. If both the assertion and reason are true but the reason is not a correct explanation of the assertion
C. If the assertion is true but the reason is false
D. If both the assertion and reason are false

Answer

A

Explanation

DNA polymerase can also remove thymine dimeas produced due to UV irradiation and fill the gap due to excision. The newly formed segment is sealed by DNA ligase.