In order to compare the figures and find the one that is not like the others, let's compare the proportion of their width and height:
[tex]\begin{gathered} A\colon \\ \frac{\text{width}}{\text{height}}=\frac{5}{4} \\ \\ B\colon \\ \frac{\text{width}}{\text{height}}=\frac{10}{8}=\frac{5}{4} \\ \\ C\colon \\ \frac{\text{width}}{\text{height}}=\frac{10}{6}=\frac{5}{3} \end{gathered}[/tex]
We can see that figure C has a different proportion, therefore figure C is the one that is not like the others.
