B!
the golden ratio is where the long side can be split into two pieces and both can still be longer than the short side of the rectangle
A. 34x2=68 which is higher than 55 so it couldn’t split into two bigger halves
B. 20x2=40 which is smaller than 45 so it could split into two bigger halves (this one does fit the golden ratio btw)
C. 18x2=36 which is bigger than 34 and couldn’t split into two larger halves
