Answer:
<h3>H2O (water)</h3><h3>N2 (nitrogen)</h3><h3>O3 (ozone)</h3><h3>CaO (calcium oxide)</h3><h3>
Explanation:</h3>
<u>H</u><u>OPE </u><u>IT</u><u> HELPS</u>
You can use the formula triangle . You can find it on google.
The most logical answer would be C.