This is the phase of matter with fixed shape and volume.

Answer: Solid

Explanation:

Solid state : It is a state in which the particles are closely packed and does not have any space between them. They have least kinetic energy due to restricted movement. This state has a definite shape and volume.

Liquid state : It is a state in which the particles are present in random and irregular pattern. The particles are closely arranged but they can move from one place to another and thus have higher kinetic energy as compared to solids. This state has a definite volume but does not have a fixed shape.

Gaseous state : It is a state in which the particles are loosely arranged and have a lot of space between them. They have highest kinetic energy. This state has indefinite volume as well as shape.

Thus the phase of matter with fixed shape and volume is solid.