in an ecosystem, there are two color varieties within a species of toads: brown and green. over 50 years, the proportion of the population that is green increases from 20% to 50%. which statement is the most likely to explain this change? (1 point) pollution caused a decrease in the proportion of brown toads. the environment changed such that toads that can jump higher into the trees to survive better. the environment changed such that green toads can blend into their surroundings better. a disease