MCQOPTIONS
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| 1. |
Which one of the following element groups was basically responsible for the origin of life on earth? |
| A. | hydrogen, oxygen, sodium |
| B. | Carbon, Hydrogen, Nitrogen |
| C. | Oxygen, Calcium Phosphorus |
| D. | Carbon, Hydrogen, Potassium |
| Answer» C. Oxygen, Calcium Phosphorus | |