The correct answer is: c) Sacred groves.
Sacred groves are patches of forests that are protected by local communities for religious or spiritual reasons. They are found in many parts of the world, including India. In Bihar, sacred groves are often located near villages and are home to a variety of plant and animal species. They play an important role in the local ecosystem and are also a source of cultural and spiritual significance.
Mangrove forests are found in tropical and subtropical coastal areas. They are characterized by their ability to grow in saline water and their unique adaptation to the harsh conditions of the intertidal zone. Mangrove forests provide a variety of ecosystem services, including protection from erosion, storm surge, and flooding; nursery grounds for fish and other marine life; and habitat for a variety of birds and other animals.
Tropical thorn forests are found in dry, tropical regions. They are characterized by their sparse vegetation and their ability to tolerate drought. Tropical thorn forests provide a variety of ecosystem services, including habitat for a variety of animals, including insects, birds, and mammals; and a source of food and medicine for humans.
Riparian forests are found along rivers and streams. They are characterized by their dense vegetation and their ability to tolerate wet conditions. Riparian forests provide a variety of ecosystem services, including flood control, water purification, and habitat for a variety of animals.