1. Question 1 Use the Dognition_aggregated_by_DogID data set for the quiz questions. Note that we use comma () to separate groups of thousands in numbers. How many unique human user IDs are there in the Dognition_aggregated_by_DogID data set? 14,433 C 16,261 Correct The Count(Distinct) aggregation is useful for addressing this question. 17,985 17,986 None of the above