Rotational symmetry means it can be rotated around the center and still be the same example: the letter O
for reflection symmetry, it has 1 line of reflection and can be reflected across that line and map on itself example: U
so the one in the middle is the one with both symmetries
alright, so the letters A,B,C,D,E,K,M,T,U,V,W,Y go in the left circle the letters N,S,Z go on the right most circle and the letters H,I,O,X go in the intersection the rest of the letters are outside