Option 1 is correct. Biosphere reserves are indeed protected areas that are specifically established for the conservation of biodiversity. These areas contain a range of ecosystems, including forests, grasslands, wetlands, and marine areas, which are crucial for the conservation of various species and genetic resources.

Option 2 is correct. Each biosphere reserve consists of three zones: the core zone, the buffer zone, and the transition zone. The core zone is strictly protected and usually serves as a reference area for scientific research. The buffer zone surrounds the core zone and is designed to provide a buffer between the core zone and human activities. The transition zone is the outermost area and is where sustainable development is promoted, along with conservation efforts.

Option 3 is correct. There is indeed a network of biosphere reserves worldwide. These reserves are designated by the UNESCO`s Man and the Biosphere Programme (MAB), which fosters collaboration among different countries to protect and sustainably manage their natural resources.

Option 4 is incorrect. Biosphere reserves were not first started by the IUCN. They were established by UNESCO`s MAB Programme in the early 1970s. The IUCN, on the other hand, is a separate organization that focuses on the conservation and sustainable use of