A translation, a reflection and a rotation
translation
The identity transformation.
An enlargement transformation will give the result of a similar shape.
A similar figure has the same interior angles as a congruent figure but its sides are in proportion to a congruent figure.
It is an enlargement
A dilation would produce a similar figure.
translation
Please don't write "the following" if you don't provide a list. We can't guess that list.
Translation, rotation, reflection.
Yes
Figures are congruent if and only if they are related by a translation, reflection, or rotation, or some combination of these transformations.
The identity transformation.
An enlargement transformation will give the result of a similar shape.
Reflections, translations, rotations.
Translation, rotation, reflection
A similar figure has the same interior angles as a congruent figure but its sides are in proportion to a congruent figure.
It will be as you term it 'horizontal stretch' in which the figure is enlarged or reduced in size.