Intermediate Mathematical Challenge 2023 Q24

A rectangle $PQRS$ has side-lengths $a$ and $b$, with $a < b$. The rectangle $PTUV$ has side-lengths $c$ and $d$, with $c < d$. Also, $a < d$ and $c < b$, as shown. The sides $RS$ and $TU$ cross at $X$.

Which of these conditions guarantees that $Q$, $X$ and $V$ lie on a straight line?