Sets
The image shows a Venn diagram of two sets M and F inside of a containing set G.
We must recall the following notations:
U = Union of sets. Everything inside of any of the sets.
∩ = Intersection between two sets. The common part of both sets.
' = Negation. Everything outside of a set or a set operation.
It's required to express in set notation the grayed part of the diagram. Note it's inside of G and outside of both M and F.
As stated above, the notation to express the union of sets is U and it's precisely the white region of the diagram. So M U F is the white part.
But we want the outside of that white part, so we use (M U F)'.
That is outside of the union, but it includes everything (the entire universe). So we must intercept that with G to take only the grayed part, so the answer is:
A. G∩(M∪F)′