<span>contain a decreasing number of organisms going from the bottom to the top of the pyramid</span>
        
             
        
        
        
The type of organisms that take energy by eating up other organisms in an ecosystem are called 'CONSUMERS'. Now these consumers are further divided into three major classes: 
1. Primary consumers: this type of consumers feed directly from the producers (plants) and they only eat grass, leaves, vegetables, etc. Such animals are also called herbivores. Example: rabbit
2. Secondary consumers: these are the animals that eat up primary consumers (animals that feed only on plants). These animals are called carnivores. Example: snake
3. Tertiary consumers: animals that eat carnivores which eats a herbivore are called tertiary consumers. They can be completely carnivore or omnivore (who feed on animals and plants both). Example: humans (they feed on animals and plants both)
 
        
             
        
        
        
Fairly sure that would be secondary succession.
        
             
        
        
        
Answer:
The answer is A.
Explanation:
The alerting system which is a part of the reticular activating system that provides the consciousness for us using the connections between the brain stem, cerebrum etc. consists of Locus Coeruleus which are nucleus located in the brain that responds to psychological stimuli such as panic, stress or discomfort. So the answer is A.
I hope this answer helps.
 
        
             
        
        
        
I pretty sure it is because the earth is bigger than the moon