What happens with electrons when atoms form covalent bonds?

Who is better, messi or cristiano, i need this for a chemistry class. asap

Which set of characteristics best describes igneous rock? a) largest type of rock, made of organic matter, hardest type of rock b) least abundant type of rock, made of other rocks, made mostly of minerals c) found on all continents, contains wavy bands of stripes, contains fossils d) most abundant type in earth's crust, made of magma/lava, contains no fossils

Describe the forces both attractive and repulsive that occur as two atoms move closer together.