Can anyone help me with this? I don’t get it.

Answer:
D
Step-by-step explanation:
A triangle with sides 2, 4.5, and 6 is similar to a triangle with sides 4, 9, and 12.
[tex] \frac{4}{2} = \frac{9}{4.5} = \frac{12}{6} = 2[/tex]