Answer: between "intelligence" and "not."
Step-by-step explanation:
The first part of this sentence is an independent clause, meaning it can stand alone as its own sentence because it has both a noun and a verb. The second half (after the comma) cannot stand alone and therefore needs to be joined to the previous sentence. The way that this question wants you to join the two together is through a comma. Another example is the sentence: "I love pizza, but I don't like calzones."
"i love pizza" can stand alone. "but I do not like calzones" cannot, so it has to be connected to the previous sentence or made so that it can stand alone with both a functioning subject-verb agreement.