Δabc was dilated from the origin by a scale factor of 2 to create δa′b′c′. which statement explains why the triangles are similar?

dilations preserve side length; therefore, the corresponding sides of δabc and δa′b′c′ are congruent.
dilations preserve betweenness of points; therefore, the corresponding sides of δabc and δa′b′c′ are congruent.
dilations preserve orientation; therefore, the corresponding angles of δabc and δa′b′c′ are congruent.
dilations preserve angle measure; therefore the corresponding angles of δabc and δa′b′c′ are congruent.