Is a collection of well defined and distinct objects.
Ex: ( A B C D E) all letters
Ex2: ( January, February, March, April) all months
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Answer: Choice D</h3>
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Explanation:
The first figure has 4 sides (quadrilateral)
The second figure has 5 sides (pentagon)
The third figure has 6 sides (hexagon)
Each time we increase the number of sides by 1.
The fourth figure must have 7 sides (heptagon). The only thing that has 7 sides is the figure listed in choice D.
