sushmitha2 wrote:
Let's say a tree starts growing and it takes 5 years to get to maturity. There could then be some trees that are far older than5 years. It would have made more sense to me if A had said that the trees can't be younger than the age of maturity. That wouldn't have been possible because they couldn't have regenerated as more trees reach maturity and block sunlight. Where am I going wrong?
I think what you explain is precisely what option A says.
Option A states that, the ages of trees do not differ much more than the length of time required to reach maturity (5 years, for instance). Consider what the argument says,
1. When white pines mature, little light reaches forest floor. (Premise 1)
2. When there is no light in the forest floor, white pines cannot regenerate. (Premise 2)
3. Conclusion --> Dense forest with nothing but mature white pines. We have to find a reason to support this conclusion.
Imagine a forest with nothing but mature white pines. If the age difference is greater than 5 years, then the pines wouldn't have grown. Tree 1 and Tree 2, lets say have the age difference of 4 years. Tree 1 starts blocking sunlight to the forest floor when it is 5 years old, thus effectively blocking the regeneration of everything in its own shade. But, Tree 2 is already 1 year old. i.e, this Tree 2 is already regenerated, so it receives some form of sunlight and continues to grow.
Hope this helps.