Answer:
D. temperature
Step-by-step explanation:
Density dependent and density independent factors work together to control the population size. Without them a population would grow indefinitely. But in real life they keep the population size stable.
Density dependent factors depend on the population size. They usually work via negative feedback loop i.e. more the members of the population, more they restrict the further growth of the population. These factors include resources which are limited like water, food and habitat space.
Density independent factors work irrespective of the population size. They will affect a big population too and a small one too. They generally include abiotic factors like temperature, weather and pH.
Hence, temperature is the correct answer.