Answer:
Option A, by having a constant supply of blood
Explanation:
Blood that flows to the muscles bring oxygen from the atmosphere to the contracting muscles where it gets consumed.  During large muscle exercise, two physiological needs arise – a) high and prolonged muscle blood flow and b) regulation of blood pressure so that there is adequate perfusion of pressure to all organs. In order to meet both the requirements, the blood flow increases so that the vasoligating muscles do not outstrip the cardiac output. 
Hence, option A is correct
 
        
             
        
        
        
C.) D<span>iscontinue the use of irrigation systems</span>
        
                    
             
        
        
        
Answer:
soarce google
Explanation:
Competition for resources like food and space cause the growth rate to stop increasing, so the population levels off. This flat upper line on a growth curve is the carrying capacity. The carrying capacity (K) is the maximum population size that can be supported in a particular area without destroying the habitat.
 
        
             
        
        
        
<span>Letter A is the answer. Almost all plant cells have single large central vacuole. These large central vacuoles of the plant cells are filled with water and can take over 80% of its cell volume. This is surrounded by a single membrane called tonoplast. The role of the central vacuole is maintaining the plant cell's pressure.</span>