Answer: Duplication
Explanation: Honestly, genetic mutations are a bit hard to grasp at first, especially since there are different terms describing them. In the provided example, you can see that the new sequence is longer than the original sequence. That said, you can compare the two to see what was added. The new sequence is almost the same as the original, except it has CA copied twice, making it longer. Therefore, this is an example of duplication.
For most questions similar to this one, you can literally just look at the bases, carefully, and see what has changed. Once you've memorized the effects of each type of mutation, you'll be able to recognize them easily.
Hope this helps :)
