B. They are able to produce their own food.
 
        
             
        
        
        
Asexual  is  where you dont need a partner and can reproduce on your own and sexually is when you need to partners to reproduce.
Hope this helps
        
             
        
        
        
Answer:
calcium is not a main element of calcium . question 2 hemoglobin is a globular protein with an embedded heme group. so a transportation protein and question 3 the building blocks of proteins are amino acids. 
Explanation:
 
        
             
        
        
        
Answer:
The correct answer is - Venom enzyme inhibitors.
Explanation:
The snake venoms are the complex mixtures of phospholipase A2s, disintegrins, serine proteases, C-lectins, and metalloproteases, and others. The snake venom phospholipase A2s (svPLA2s) enzymes found in most of the families of venomous snakes that cause anticoagulant effects, cardiotoxicity, neurotoxicity, and cytotoxicity, and other effects.
In antivenom, there are Venom enzyme inhibitors other than antibodies that help in neutralizing these enzymes by weakening or inhibiting these toxic actions.
 
        
             
        
        
        
Answer:
 a. commensalism is the correct answer.
Explanation:
By growing on the trunk or branch of a tree, a lichen gains height and exposure to sunlight for photosynthesis. The tree is not harmed by the lichen but does not benefit either. The relationship between the lichen and the tree is commensalism.
Commensalism is a relationship between two organisms where one organism gets benefits from other organisms without causing any harm or any damage from the relation as it one side symbiotic relation.
In this, we can see lichen is getting benefits from the tree. 
for example, lichen is getting following benefits from the tree such as ( a lichen gains height and exposure to sunlight for photosynthesis.) and they are causing any harm to tree neither any benefits so this is a one-side symbiotic relation and thus the relationship is an example of commensalism.