The main idea of the coastal mangrove passage is

• A. Mangroves are decorative.
• B. Mangroves provide physical protection and ecological services worth conserving.
• C. Mangroves hinder economic development.
• D. Mangroves only exist in tropical regions.

Answer: (B)

At the heart of the passage is the idea that coastal mangroves provide real, tangible benefits—physical protection from storms and erosion, along with ecological services—that make conserving them worthwhile. The text explains how mangrove roots slow and dissipate wave energy, trap sediments, reduce coastal flooding, and serve as nurseries for fish, supporting biodiversity and local livelihoods. This combination of protection and ecosystem services is the main message, not aesthetics or hindrance to development, and it does not claim mangroves exist only in tropical regions. That’s why the statement about mangroves providing protective benefits and ecological services worth conserving is the best fit.