Answer:
B.
Step-by-step explanation:
If the given right triangles are similar, that meanst they have a ration in common, that is, one of them can be double size the other one. In other words, they are related by a scale ratio.
Notice, that one hypothenuse is double the other one, that is, 10 is double than 5. Also, 8 is double than 4. This means the scale factor is 2, one triangle has double size than the other.
Therefore, the proportion that relates these triangles is
[tex]\frac{10}{5} =\frac{8}{4}=2[/tex]
or
[tex]\frac{4}{8}=\frac{5}{10}=\frac{1}{2}[/tex]
Therefore, the right answer is B.
