Answer:
D. 3
Explanation:
The scale factor used to transform right triangle ABC into right triangle A'B'C' is the ratio of any corresponding side length of ∆A'B'C' and ∆ABC.
Thus, using the ratio of side length A'B' to side length A'B', we can get the scale factor as follows:
A'B' = 12 - 6 = 6 units
AB = 4 - 2 = 2 units
Scale factor = A'B' : AB = 6 : 2 = 6/2 = 3