The correct option is A Both A and R is true. R is the correct explanation for A.
Mangroves are incredibly productive in coastal ecosystems. But, they also play another important role for humans, i.e., protecting communities from major storms. With rising temperatures, the frequency and intensity of hurricanes and cyclones are also increasing. Mangrove trees break up the force of a storm by absorbing some of the energy from the cyclones. Thus, they protect the coasts from cyclone damage. Efforts are needed to preserve mangrove forests as they are one of the world's most threatened tropical ecosystems.