Resistance against infection developed through a series of vaccine doses represents a case of:
a. artificially acquired passive immunity
b. naturally acquired passive immunity
c. artificially acquired active immunity
d. naturally acquired active immunity

The answer is C my teacher explain this to us in class and i had the same question on usa test prep

i think it's they require warm air

explanation:

tornados usually happen when it's raining right so when it's raining it cools down so if the temperature keeps changing then i think a tornado occurs sorry if it's wrong

the correct answer is:

a population changes in response to a change in the environment.