Quarks are thought to be the basic component of

Answer : The correct answer is- Hadrons.

Explanation -

Quarks are the sub sub-atomic particles of an atom, which have fractional positive and negative charge.

Hadrons are made up of quarks.

For instance, proton that is made up of two up quarks and one down quark.

Another hadron neutron is made up of two down quark and one up quark.

Thus, hadron is the right answer.