1.) why does carbon form covalent bonds?

it tends to pull 4 electrons from another atom.
it tends to release 4 electrons to another atom.
it will usually bond to multiple atoms which can provide a total of 4 additional electrons.
it has a strong electronegativity.

2.) what type of bond will be formed for atoms that have a +1 or -1 charge?

covalent
ionic
they do not react
elemental

3.) select all that apply.

the relative ionic or covalent character of chemical bonds may be estimated by:

the total number of electrons for each element
the addition of electronegativities
comparison of the associated families to which the elements belong
the difference in electronegativities

For #1, I'd say it's "It will usually bond to multiple atoms which can provide a total of 4 additional electrons."

2. Ionic (I'm quite certain because anions/cations (-1 & +1) are Ionic from what I recall, if that's true it's Ionic.
3. "comparison of the associated families to which the elements belong" and
"the difference in electronegativities" are what I would choose, as I mentioned in a comment earlier.

If I'm wrong let me know, but I am at least 80% sure that these responses are correct from what I remember in Chemistry.

Explanation:

1).    A bond, that is, formed by sharing of electrons between the combining atoms is known as a covalent bond.

For example, atomic number of carbon atom is 6 with electronic distribution 2, 4.

So, in order to completely fill the octet carbon atom will combine with atoms that can provide 4 additional electrons to a carbon atom.

Hence, carbon form covalent bonds because it will usually bond to multiple atoms which can provide a total of 4 additional electrons.

2).   When an atom loses one electron then it acquires a +1 charge. Whereas when an atom tends to gain one electron then it acquires a -1 charge.

An ionic bond is formed when there is transfer of electrons from one atom to another.

For example, fluorine on gaining one electron will form a ion and sodium on losing an electron will form a ion.

Therefore, we can conclude that ionic bond will be formed for atoms that have a +1 or -1 charge.

3).    When there is great difference in electronegativity of combining elements then it also results in the formation of an ionic bond. This is because difference in electronegativity causes partial positive charge on cation and partial negative charge on anion.

Also, families of the combining elements help in determining the difference in electronegativity.

Thus, we can conclude that the relative ionic or covalent character of chemical bonds may be estimated by: