Aristotle first proposed that was at the center of the solar system.
a.
the sun
c.
earth
b.
the moon
d.
jupiter

Earth

Explanation:

Before the Heliocentric theory, Ptolemy's and Aristotle's geocentric model of the solar system was popular. Geocentric model considers Earth as the center of the solar system with stars, planets, sun and moons revolving about it in concentric orbits. This model was supported by the observation that the sun seemed to go about the Earth in every 24 hours.

On the other hand, Copernicus proposed Heliocentric model- having sun at the center of the solar system.

you didnt put any of the following

considering the question as per the attachment

here we can see that the radon nuclide has 222 as the atomic mass number and 86 as the atomic number.

when it undergoes nuclear fission it gives polonium which has atomic mass number as 218 and atomic number will be 84 along with a helium nucleus which has 4 atomic mass number and 2 as its atomic number.

222 = 218 + 4 (atomic mass number)

86 = ? + 2; therefore ? = 86-2 = 84.

the atomic mass number of polonium will be 84.