Answer:
Option C.
Step-by-step explanation:
From the picture attached,
ΔA'B'C' is a dilation of ΔABC which means image ΔA'B'C' is similar to ΔABC.
By the property of similarity corresponding sides of both the triangles will be proportional.
[tex]\frac{\text{AB}}{\text{A'B'}}=\frac{\text{BC}}{\text{B'C'}}=\frac{\text{AC}}{\text{A'C'}}[/tex]
[tex]\frac{AB}{6}=\frac{15}{10}[/tex]
AB = [tex]\frac{6\times 15}{10}[/tex]
AB = [tex]\frac{90}{10}[/tex]
AB = 9 units
Therefore, length of side AB = 9 units.
Option C. will be the answer.