Answer : The phase of matter can be changed by pressure and temperature.
Explanation :
As we know that there are three states of matter which are solid, liquid and gaseous state.
Solid state : In this state, the molecules are arranged in regular and repeating pattern and are closely packed that means they are fixed and vibrate in place but they can not move from one place to another.
Liquid state : In this state, the molecules are present in random and irregular pattern and are closely packed but they can move from one place to another.
Gaseous state : In this state, the molecules are present in irregular pattern and are not closely packed and they can move freely from one place to another and spread out.
From this we conclude that, the arrangements of all the phase of matter can be changed by applying the pressure and temperature. That means,
By applying the pressure and temperature, the solid phase can be changed into liquid or gaseous state or liquid into solid or gaseous or gas into liquid or solid.
Hence, the phase of matter can be changed by pressure and temperature.