Answer
The order in which the points of the triangles are listed identify the corresponding parts.
Work Step by Step
$\Delta$$MNP$$\sim$$\Delta$$RST$
The triangles have the same angle measurements and same side length ratios, but different side length measurements. The points/letters on the triangles indicate how these two similar triangles are drawn to correspond with each other.
$M$ and $R$, $N$ and $S$, and $P$ and $T$ correspond with each other.
The triangles are drawn so that these points line up to have the the same angle measurements and side length ratios, making them similar.