Answer: Choice D) set of even integers
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Explanation:
U = universal set = {all positive integers} = {1, 2, 3, 4, 5, ...}
A = {stuff in set U that is odd} = {1, 3, 5, 7, 9, ...}
= {stuff in set U but NOT from set A} = {2, 4, 6, 8, ...}
= {set of even numbers from set U}
In set theory, the complement is simply the complete opposite. If the number 7 is found in set A for instance, then 7 is not going to live in the complement
The opposite of the odd numbers is the set of even numbers.
Therefore, we go for <u>choice D</u> as our final answer.
Side note: if we union set A with its complement then we get the universal set as a result.