Final answer:
The population dynamics of collared lemmings in Greenland are best described by population cycles, with regular fluctuations in size. They do not exhibit exponential or logistic growth patterns typically. An example of exponential population growth is bacteria growing in a lab's enriched medium.
Step-by-step explanation:
The pattern of population dynamics that best describes that exhibited by collared lemmings in Greenland is B. Population cycles. This pattern is characterized by regular fluctuations in population size over time. These fluctuations can be caused by various factors, including changes in food availability, predation, disease, and climate conditions, leading to periods of increase followed by declines in the number of lemmings. Collared lemmings do not exhibit exponential growth, which is described as a continual rapid increase in population size without constraints. Neither do they show logistic growth, which involves a population increasing until it reaches the carrying capacity of the environment and then leveling off.
As for an example of exponential population growth, it could be c. bacteria growing in an enriched medium in a lab. In such a controlled environment, bacteria typically have abundant resources and space to grow, often doubling their numbers rapidly and continuously.
If the major food source of seals declines due to pollution or overfishing, it is likely that the seal population would be negatively affected, potentially leading to a decrease in their numbers due to the increased competition for the remaining food resources and a higher risk of starvation.