Which type of particle acts as a force mediating particle?

The correct choice is boson, as these particles are essential in mediating forces in the universe. Bosons are characterized by their integer spin (0, 1, 2, etc.), which allows them to facilitate interactions between other particles. For instance, photons are bosons that mediate the electromagnetic force, while W and Z bosons are responsible for the weak nuclear force. This role of bosons as force carriers is a fundamental concept in quantum field theory, where they act as the "glue" that transmits the fundamental forces between matter.

Baryons, which are made up of three quarks, and fermions, which include particles like electrons and quarks with half-integer spin, do not serve this mediating role. Likewise, leptons, which include electrons and neutrinos, are matter particles and also do not mediate forces. Understanding the distinct roles of these particle types is crucial for grasping the structure of matter and the fundamental forces that govern interactions in the universe.