What is an atomic nucleus?

a.)the outer part of an atom in which electrons move
b.)the outer part of an atom in which neutrons move
c.)the central part of an atom, composed of protons and neutrons
d.)the central part of an atom, composed of protons and electrons

The correct option is (C).

Explanation:

An atom is a smallest unit of the matter. Atom consists of electrons, protons, nucleus and neutrons.

Nucleus is the central part of the atom where the whole mass of the atom is supposed to be concentrated.

The electrons revolve around the nucleus. They are negatively charged particle.

The protons are located in the nucleus. They are positively charged particle.

The neutrons are located in the nucleus. They are neutral charged particle.

Therefore, an atom nucleus is the central part of an atom, composed of protons and neutrons.

the first american roller coaster was the mauch chunk switchback railway, built in the mountains of pennsylvania in the mid-1800s. the track, originally built to send coal to a railway, was reconfigured as a "scenic tour."

there is no correct list among the choices you've provided.

the list might look something like this:

-- baby human

-- piccolo

-- flute

-- soprano singer

-- trumpet

-- tenor singer

-- trombone

-- baritone singer

-- baritone horn

-- bass singer

-- tuba

since i had to make up the list myself, i made it easy on myself, and i didn't try to shuffle the string instruments and woodwinds into it too.