Answer:
QUARKS
Explanation:
Quarks are usually defined as a small particle that binds up protons and neutrons by a strong force of attraction. These form the fundamental particles in physics. These are comparatively heavier than the electrons and the size of these particles is approximately 10^−18 m. These are formed by more finer particles that are commonly known as 'preons'.
There are mainly six types of quarks and they are as follows-
top, bottom, up, down, strange, and charm