Understand Line Segment Transformation Properties Practice Test

A student says: “If you rotate a segment $90^\circ$, its length might change because it points in a different direction.” Which statement best corrects the student?

A student draws segment $QR$ from $Q(-4,-2)$ to $R(-1,2)$. Then the student translates it by $(+5,-3)$ and reflects the result over the $y$-axis to get $Q''R''$. What is the length of $Q''R''$?