Identify the correct statement regarding the pineal gland or the hormone secreted by it:
| 1. | The gland is situated on the ventral side of the forebrain |
| 2. | The hormone secreted by the gland is called as melanin |
| 3. | The hormone regulates the diurnal rhythm of our body |
| 4. | The hormone decreases immunity |
| I: | helps in maintaining the normal rhythms of sleep-wakefulness cycle and body temperature. |
| II: | influences metabolism, pigmentation and the menstrual cycle. |