Organismal Theory.
The answer is not Cell Theory because cell theory constitutes to life itself where the organismal theory does not.
Hope this helps!
4. be cut by the same restriction enzyme
Mainly because our lungs are made to intake air, and if we where to inhale water we would drown. oxygen can only be obtained from the air because our lungs would be able to expell the excess stuff from air easier than in water. hope i helped.