You are presented with the question "The growth in what comes from primary and secondary meristems can be measured with a ruler?" and the following answer choices: 
- bushes
 - years
 - Trees
 - three
 - roots
 - bamboo
 - rings
 - a prism

Now knowing that roots have primary and secondary meristems for growth in length and width and rulers are used to measure length, choose the best answer.


 

     roots    