Answer:
The correct answer is d. environmental factor
Step-by-step explanation:
Environmental factors are the variables which are present in the surrounding that influence the living organisms like temperature, pressure, humidity, sunlight, pH. Environmental factors influence the growth and survivability of organisms.
Extreme heat is an environmental factor which occurs due to higher temperature in the environment and affects living organisms, for example, extreme heat can cause over exhaustion during playing tennis. So being unable to play tennis due to extreme heat is an example of environmental factors. So the right answer is d.