Question

the small, dense core at the center of an atom is the
select one:
a. electron
b. nucleus
c. neutron
d. proton

Explanation:

In atomic structure (a topic in Natural Science, specifically Chemistry or Physics), the atom has a small, dense core at its center called the nucleus, which contains protons and neutrons. Electrons are outside the nucleus, protons are part of the nucleus, and neutrons are also part of the nucleus but the term for the core itself is nucleus.

Answer:

b. nucleus