In which phase transition do molecules directly move from a state involving vibration of particles in a fixed position to a state involving random movement of high-speed particles?

The phase transition in which molecules directly move from a state involving vibration of particles in a fixed position to a state involving random movement of high -speed particles is called : Sublimation

Particles in a fixed position = solid particle
Random movement high speed particles = gas particles

The transition from solid to gas is called sublimation

hope this helps

The correct answer is  b)