Planets orbit the sun because
the law of universal gravitation suggests the greater the mass of two objects, the greater the gravitational attraction between them
the law of equal areas suggests planets must orbit the sun in equal areas and equal times
the harmonic law suggests that the closer the planet is to the sun, the longer is its orbit about the sun
the law of universal gravitation suggests the greater the distance between objects, the greater is their gravitational

This is a poorly written question.

Out of the choices listed, the first one is the only one that includes
a true statement ... the greater the mass of two objects, the greater
the gravitational attraction is between them. 

-- Newton's law of universal gravitation doesn't "suggest" that.  It states it ...
boldly and unequivocally.

-- The law doesn't refer to the "greatness" of the mass of the two objects. 
It refers to the product of their masses.

-- It's true that the law of universal gravitation can be massaged and
manipulated to reveal the existence of gravitational planetary orbits.
But there's a lot more to it than simply the masses.

For example ... the gravitational force between two objects is inversely
proportional to
                           (the distance between the objects)² .

It turns out that IF that exponent were not precisely, exactly  2.000000... ,
then gravitational orbits could not exist.

Learned about life itself