Identify the given nitrogenous base:
| 1. | Adenine | 2. | Guanine |
| 3. | Thymine | 4. | Cytosine |
| I: | are polynucleotides. |
| II: | are constituents of the true macromolecular fraction of any living tissue or cell. |
| 1. | Phosphate group | 2. | Ribose sugar |
| 3. | Fatty acid | 4. | Nitrogenous base |