Thymine and cytosine are classified as "Pyrimidines" and have one ring of carbon and nitrogen atoms for each base.
A. objects made of crystals minerals water and air
Process of elimination-
there isn’t organic matter in rocks so D is out
they are made of minerals so B is out
some types of rock (pumice) have air bubbles in them so A is more likely than C
Answer:
C.) Covalent
Explanation:
Oxygen and carbon are both nonmetals.
A.) is incorrect because hydrogen bonds are only formed between hydrogen and either oxygen, nitrogen, or fluorine.
B.) is incorrect because ionic bonds form between nonmetals and metals. In this situation, you have two nonmetals.
C.) is correct because covalent bonds are formed between two nonmetals. A covalent bond will form because oxygen and carbon are nonmetals.
EEG or Electroencephalogram.
