In situ conservation is on-site conservation or the conservation of genetic resources in natural populations of plant or animal species, such as forest genetic resources in natural populations of tree species. It is the process of protecting an endangered plant or animal species in its natural habitat, either by protecting or cleaning up the habitat itself, or by defending the species from predators. It is applied to conservation of agricultural biodiversity in agro ecosystems by farmers, especially those using unconventional farming practices. Insitu conservation includes national parks, sanctuary and biosphere reserve.
Botanical gardens comes under exsitu conservation. Thus, option C is correct and other options are wrong.