Hello there! The answer would be B) translation and dilation.
When shapes are congruent, they are the same shape and size. To be changed where the shapes are no longer congruent , the size or shape has to change. In the options you've provided, B would be the correct option since it is the only one that includes changing size, when mentioning dilation (or making something bigger, hence changing it's size). In the other options, which include reflection and translations and rotations, they just change the placement of the shape, but other than that the shape is the same as the others.
I hope this helps, have a great day!
