The key to understanding what the question requires is to pay atention to the details given to us in the question:
I. We have a triangle
II. We want to construct a similar triangle
III. The triangle in II is to be similar but not congruent (of identical sizes)
To achieve the following, we must understand the varying types of transformations available
Rotation means that the shape is turned about a fixed point (the center of rotation); the shape remains the same size, only its direction is changed
Reflection means that all the vertices of a figure are flipped (kind of like a mirror image); the shape remains the same size, only its direction is changed
Translation means that the figure is moved in a straight line; the shape remains the same size, its direction/orientation remains the same
Dilation means that the figure is of a different size; the shape remains the same, the size is different
Hence, the correct answer is Reflection and Dilation (option C)