Changes of state

The table shows the melting and boiling points of four substances.

Substance W: melts at $-10^\circ\text{C}$, boils at $40^\circ\text{C}$

Substance X: melts at $5^\circ\text{C}$, boils at $120^\circ\text{C}$

Substance Y: melts at $80^\circ\text{C}$, boils at $150^\circ\text{C}$

Substance Z: melts at $-50^\circ\text{C}$, boils at $-20^\circ\text{C}$

At $25^\circ\text{C}$, which substance is in the liquid state?