Why is gravity the dominant force among planets?

But when we are talking about larger scales, like astronomical ones, gravity is dominant. The main reasons for this are that gravity has a longer range than the other forces (this shows that distance is important in both cases), and the second reason is that there is nothing in existence with negative mass.

i'm assuming that the correct answer is indeed the first one/ "a"..

answer is: naturally occurring solid, inorganic compound or element is mineral.

minerals usually have crystalline form, that means than crystal constituents (atoms, molecules or ions) are arranged in a highly ordered microscopic structure, forming a crystal lattice that extends in all directions.

for example magnetite is a mineral of iron oxide (fe₂o₃).

calcite is a carbonate mineral and the most stable polymorph of calcium carbonate (caco₃).

dolomite is an   carbonate mineral composed of calcium magnesium carbonate (camg(co₃)₂).