Answer:
The answer that corrects the fragment is "Pets can make good gifts for children if the gift giver chooses the pet carefully."
Explanation:
Fragments are disconnected sentences from their main idea normally by the misuse of a period or comma, The original groups of words given are two separated sentences, by deleting the period between them we can have a full idea that follows the structure of fist conditional where we have the if clause that represents the condition or hypothetical situation, and the result that's the main clause. by making this change we will stop having fragments and we will have a correct first conditional sentence.