Coastal wetlands and mangroves play a crucial role as:

The correct answer is: d) All of the above.

Coastal wetlands and mangroves play a crucial role as breeding grounds for fish, nutrient-rich habitats, and natural filters.

• Breeding grounds for fish: Coastal wetlands and mangroves provide a safe and sheltered environment for fish to spawn and grow. The roots of mangroves provide a place for fish to lay their eggs, and the muddy sediment in these areas is rich in nutrients that help fish larvae grow.
• Nutrient-rich habitats: Coastal wetlands and mangroves are also important habitats for other marine life, such as shellfish, crabs, and shrimp. The muddy sediment in these areas is rich in nutrients that these animals need to survive.
• Natural filters: Coastal wetlands and mangroves also help to protect the coastline from erosion and flooding. The roots of mangroves help to stabilize the shoreline, and the muddy sediment in these areas helps to absorb wave energy.

In addition, coastal wetlands and mangroves play an important role in the global carbon cycle. They absorb carbon dioxide from the atmosphere and store it in their tissues. This helps to reduce greenhouse gas emissions and mitigate climate change.

Overall, coastal wetlands and mangroves are essential ecosystems that provide a variety of benefits to humans and the environment.