Answer: Choice C) integers from 1 to 10 inclusive
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Explanation:
The "U" means "set union". We form a larger set that contains any number that's in set A, set B, or both.
So,
A U B = {stuff from set A, stuff from set B}
A U B = {1,3,5,7,9, 2,4,6,8,10}
A U B = {1,2,3,4,5,6,7,8,9,10}
A U B = set of integers from 1 and 10 inclusive
That makes choice C the final answer.
Choice B is very close to it, but that verbally describes the set {2,3,4,5,6,7,8,9} which leaves out 1 and 10. The "inclusive" makes sure to involve the endpoints 1 and 10, as well as everything in between.
