Answer:
Pre image of B' is B
Explanation:
Given:
ABC is a triangle
A transformation is done on ABC so that the image is A'B'C'.
Note that transformations are of various types such as dilation, vertical shift, horizontal shift, rotation about a point, reflection on a line, etc.
In any type of transformation, corresponding vertices will be matched. In other words, A will become A', B will become B' and C will become C'.
Because of the property of the transformation to keep images similar and also transforming correspondingly the vertices we get preimage of B' would be nothing but B itself.