Identify a pair of molecules having similar shapes of both members.

Molecular shapes are determined using Valence Shell Electron Pair Repulsion theory, analyzing bonding pairs and lone pairs around the central atom.

$\text{NH}_3$ has trigonal pyramidal geometry (steric number 4, 1 lone pair), while $\text{SO}_2$ is bent (steric number 3, 1 lone pair)—different shapes.

$\text{XeF}_4$ is square planar (steric number 6, 2 lone pairs), while $\text{SF}_4$ is see-saw (steric number 5, 1 lone pair)—different shapes.

$\text{PCl}_5$ is trigonal bipyramidal (steric number 5, 0 lone pairs), while $\text{BrF}_5$ is square pyramidal (steric number 6, 1 lone pair)—different shapes.

$\text{H}_2\text{O}$ and $\text{SCl}_2$ both possess tetrahedral electron geometry with two bonding pairs and two lone pairs, resulting in identical bent molecular geometries.