A gas is enclosed in a cylinder by a movable piston. The gas column has a length of $20\,\text{cm}$ and the pressure in the cylinder is $p$. The piston is drawn out by $30\,\text{cm}$, making the gas column length $50\,\text{cm}$. The temperature of the gas remains unchanged. What is the gas pressure now?
- A$0.40p$
- B$0.60p$
- C$1.5p$
- D$2.5p$