Answer:
A. City A because there are no pollution sources upstream.
Explanation:
Water pollution is th contamination of water. There are many means through which water is contaminated such as industrial waste, agricultural waste and domestic waste et-cetra.
City A and City B get water from sunset lake and moth lake which have factories (industrial waste) and farmland (agricultural waste) nearby them, which are responsible for the contamination of river water. due to this cities can recieve contaminated water which can affect their health.
But the quality of water in City A will be best than that of City B because according to the image, City A do not have nay upstream soooooource of pollution, as factories and farmland are located at downstream.
Hence, the correct option is A.
 
        
             
        
        
        
Answer:
it is every organisms goal to "survive and repopulate" therefore, with natural selection the weaker organisms die because they did not possess the traits necessary to survive, and the strong survive and repopulate 
Explanation:
 
        
             
        
        
        
Iron is a chemical element with symbol Fe and atomic number 26. It is a metal in the first transition series. It is by mass the most common element on Earth, forming much of Earth's outer and inner core
        
                    
             
        
        
        
In diagnosing thyroid disease, thyroid function must be established first. This can be done by testing for the TSH, T4 and T3 in the serum. After testing for the thyroid function, ultrasound must be done, this can help us to visualize if the nodules are cystic or solid. Ultrasound can also help establishing the size of the tumor as well as if there is an invasion. FNAB can be done to determine the presence of malignancy, before doing this patient must be in euthyroid state. Hyperthyroid patient can lead into thyroid storm if FNAB was done without knowing the thyroid function of the patient.