Fact 1: Secondary meristem is located within and around the vascular tissues.

Fact 2: Secondary meristems make the stem or root grow larger in diameter.

Given the two facts above, answer the question "What make the stem or root grow larger in diameter?" with the following options: 
- heart cells
 - rainfall
 - bending light rays
 - vascular tissues
 - tissue boxes
 - plant cells
 - colors of the spectrum
 - Exfoliation


 

    vascular tissues     