Classification is subject to change because science is an evolving subject. New things are discovered every year and thus changing the way we understand the world around us.
Answer:
The correct option is number 3. A deficit of appositional bone growth would not be life threatening.
Explanation:
Appositional bone growth can be defined as the thickening of the bones due to increase in the number of bone tissues at the surface. In this kind of bone growth, the diameter of the bone increases rather than the length of the bone. This can lead to deformation of the bone but it is not life-threatening.
Rest of the options 1, 2 and 3 are serious disorders and can eventually lead to death.
8H2. The actual equation doesn't make sense for 8H2. This is because in compounds it always says the number of atoms after the element symbol, but in this case, there is an 8 before it. This means that it isn't a compound.