Covalent bonds usually bond atoms of which type of elements together?

a. metals to metals
b. metals to nonmetals
c. nonmetals to nonmetals
d. metals to metalloids

Covalent bonds hold non-metallic atoms together. These atoms have many electrons in their outermost level and have a tendency to gain electrons rather than to yield them.  

In this case the bond is formed by sharing a pair of electrons between the two atoms, one from each atom. Then, this pair of shared electrons is common to the two atoms and holds them together, so that both atoms acquire more stability.

Therefore the correct answer is C.

i believe the answer would be:

d. violin, clarinet, french horn, and tuba

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