Answer: {t,h,s} which is choice A
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Explanation:
We start with set M = {m,a,t,h,s}
Then we cross off any letter we find in set N
So we'll cross off the 'm' and 'a' since they are both in N. We're kicking these letters out of the set.
We go from {m,a,t,h,s} to {t,h,s}
We leave t,h and s alone as those letters aren't in set N. So we don't kick them out.
