Given here are four sentences. The first sentence is in correct order while the rest of the sentences are jumbled. Pick the option that gives their correct order.
A. Environmental engineers are always trying to find solutions to the problem of pollution.
B. They also have to deal with medical waste and radioactive leakages.
C. The pollution caused by chemicals, oil spills, hazardous and toxic waste is especially dangerous.
D. We can help them by avoiding such pollutants and by segregating waste for easy processing.