You are presented with the question "What can be used to estimate a forest's growth rate?" and the following answer choices: 
- rings
 - fibers
 - bamboo
 - bark
 - crown
 - wind
 - soil
 - traits

Now knowing that the number of rings in a tree trunk can be used to estimate the age of the tree and tree rings are examined to learn the forest age and growth rate, choose the best answer.


 

 rings        