Here's some advice;
take notes, pay attention in class, and use your textbook, if you can't find the answer look on the web, ask a friend, but never use brainly because people will say random stuff to get points.
 
        
             
        
        
        
I think the correct answer is receptor. To respond to a chemical signal a cell must have a receptor and also this where the signaling molecule can bind.  A receptor is a protein molecule that can receive signals from the outside environment of the cell.
        
             
        
        
        
first one is definitely a fact
 
        
                    
             
        
        
        
Answer:
I would say B.
Explanation:
A would only fix biodiversity temporarily, until humans come and wipe them out again. C is just kind of impossible, and containing them could also be problematic. D is also unreasonable, and some animals would not be able to thrive in new ecosystems. B would help save the environment, which would save the animals, which would help biodiversity.