Consider the two statements:
| I. | Moulting may be responsible for 80 to 90% of all arthropod deaths. |
| II. | The exoskeleton cannot stretch and thus restricts growth and hence moulting. |
| 1. | Both I and II are correct and II explains I |
| 2. | Both I and II are correct but II does not explain I |
| 3. | Only I is correct |
| 4. | Both I and II are incorrect |