The enzyme that can proofread replicating DNA, detect incorrect bases, excise them, and correctly replace them is .

The correct answer is: DNA polymerases.

Explanation:

DNA polymerases, while are more commonly known for being the enzymes that synthesize the new strands of DNA during the process of Replication, but they also partake in the important task of proofreading the newly-synthesized strand of DNA, detecting errors in the process of matching the base pairs and also replacing them.

To achieve this, the DNA polymerase detects the incorrect nucleotide, removes it with its 3'-5' exonuclease activity, and then replace it with the correct nucleotide.

In the process of mismatch repair, a piece of the new DNA strand is removed by the DNA polymerase, then replaced with the correct base pairs, and then the ends are sealed by the enzyme DNA ligase.