The most important strategy for the conservation of biodiversity together with traditional human life is the establishment of

Biosphere reserves are the right answer because they are the one protected-area category designed to conserve biodiversity alongside people. Under UNESCO's Man and Biosphere (MAB) programme, each reserve is zoned into a core area (strictly protected), a buffer zone (regulated use, research, eco-tourism) and a transition area where settlements, agriculture and traditional practices continue. That zoning is why the question says 'together with traditional human life'.

• B) Botanical gardens are ex-situ collections of plants, useful for research and display, but they exclude the surrounding human community altogether.
• C) National parks give strong legal protection under the Wildlife (Protection) Act, 1972, where grazing, human settlement and extraction of forest produce are generally barred. Human life is pushed out, not integrated.
• D) Wildlife sanctuaries also fall under the Wildlife (Protection) Act, 1972 and allow some limited rights, but they focus on wildlife rather than a whole-landscape approach that includes people.

Core concept: in-situ conservation through zoning. Mains angle: the tension between conservation and the livelihoods of forest-dwelling communities, which the Forest Rights Act, 2006 tries to address. The number of biosphere reserves in India has grown since 2014, so verify the current list before relying on any count.

Trap: choosing national parks because they sound like the strongest protection. Strength of protection is not the same as integrating people, and the question is asking about the second.