A large population of a certain species of toad lives in the tropical region of South America. These toads feed on worms and insects. A disease-causing fungus species that thrives in hot climates also exists in the same ecosystem. Which of the following most likely causes the decrease in the population of the toad species in this ecosystem? A. an increase in urbanization in the ecosystem B. an increase in temperature in the ecosystem C. a decrease in pressure in the ecosystem D. a decrease in air currents in the ecosystem