Fact 1: Cartilage is a tough tissue that contains a protein called collagen.

Fact 2: Collagen tissue is made by collagen fibers connected by bridges.

Given the two facts above, answer the question "What is a tough tissue made by fibers connected by bridges?" with the following options: 
- a prism
 - bones
 - arms
 - roots
 - skin
 - homogenous
 - cartilage
 - alveoli


 

       cartilage  