Answer: choice C
Step-by-step explanation:
The union of events A and B, denoted ∪ , is the collection of all outcomes that are elements of one or the other of the sets A and B, or of both of them. It corresponds to combining descriptions of the two events using the word “or.”
**keep in mind that we don’t write numbers more than once in these sets(choiceB)
so the answer would be
{3,4,5,6,7,8,9}
