Smallest fraction

Which of these is the smallest?

Problem



Which of these is the smallest?

$$\frac{2+3}{4+6}\hspace{30mm}\frac{2\div3}{4\div6}\hspace{30mm}\frac{23}{46}\hspace{30mm}\frac{2-3}{4-6}\hspace{30mm}\frac{2\times3}{4\times6}$$

This problem is taken from the World Mathematics Championships