Final answer:
A deaminated cytosine turning to uracil leads to a transition mutation, which replaces a G-C base pair with an A-T pair. The correct answer is A) Transition mutation.
Step-by-step explanation:
When a cytosine is deaminated, it becomes uracil. This alteration can lead to a mutation during DNA replication because uracil pairs with adenine instead of guanine. The end result is that a guanine-cytosine (G-C) base pair is replaced by an adenine-thymine (A-T) base pair. This type of mutation is known as a transition mutation, which is when a pyrimidine (in this case, cytosine) is replaced by another pyrimidine (uracil, which in DNA pairing terms leads to thymine) or a purine is replaced by another purine.
Therefore, the correct answer to the given question is A) Transition mutation, as deamination of cytosine to uracil is typically corrected by the base excision repair mechanism, leading to a transition if left uncorrected. In contrast, a transversion mutation involves a pyrimidine becoming a purine, or vice versa.