Answer:
D. Paragraph 7
Step-by-step explanation:
This is an essay "Searching for the Blue Poison Dart Frog" by Kyle Ellington.
It consists of seven paragraphs; the first describing their locaton (the rainforest) and their quest (finding the given frog), the second and third introducing us to this peculiar little animal, the fourth describes the author's impressions of this trip, the fifth describes the moment they located the animal, the sixth is the depiction of the frog's appearence and the seventh is the conclusion and looking back on this journey.
Since, in the given sentence, the author states that he made the right decision, this means that it belongs in the final paragraph, since it's the reflection on the hard journey after the search was completed.