<span>d. All of the above
These behaviors;
Spreading wings
Flattening feathers
panting
are all evolutionary process to maintain body temperature. Birds are warm-blooded animals. Also known as </span><span>homeotherms, which is defined as having the constant body temperature. This is a vital function for the survival of the specie.</span><span>
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Answer:
The given blank can be filled with cytokine storm. 
Explanation:
Generally, influenza is self-restricting. Though serious cases can result in pneumonia and other issues, which can be deadly. However, such cases are very common in the elderly and in very young individuals. There are certain strains of the influenza virus, which are more dangerous to young adults in comparison to old or very young.  
The strains, which influence young adults are considered to comprise a cytokine storm, that is, a positive feedback loop, which produces in between the production of cytokines and leukocytes. This cytokine storm generates an acute inflammatory reaction, which results in brisk accumulation of fluid in the lungs, resulting in pulmonary failure. The very young or very old are less vulnerable to this influence as their immune systems are less strong.  
 
        
             
        
        
        
Explanation:
Edit
An ecological pyramid (also trophic pyramid, Eltonian pyramid, energy pyramid, or sometimes food pyramid) is a graphical representation designed to show the biomass or bioproductivity at each trophic level in a given ecosystem.
A pyramid of energy represents how much energy, initially from the sun, is retained or stored in the form of new biomass at each trophic level in an ecosystem. Typically, about 10% of the energy is transferred from one trophic level to the next, thus preventing a large number of trophic levels. Energy pyramids are necessarily upright in healthy ecosystems, that is, there must always be more energy available at a given level of the pyramid to support the energy and biomass requirement of the next trophic level.
A pyramid of energy shows how much energy is retained in the form of new biomass at each trophic level, while a pyramid of biomass shows how much biomass (the amount of living or organic matter present in an organism) is present in the organisms. There is also a pyramid of numbers representing the number of individual organisms at each trophic level. Pyramids of energy are normally upright, but other pyramids can be inverted or take other shapes.
Ecological pyramids begin with producers on the bottom (such as plants) and proceed through the various trophic levels (such as herbivores that eat plants, then carnivores that eat flesh, then omnivores that eat both plants and flesh, and so on). The highest level is the top of the food chain.
 
        
             
        
        
        
It would be D. Water molecules are split apart and the byproduct of that would be the O2. As energy enters the chloroplasts, the energy excited the H2O molecules and causes them to split