Ex situ conservation include:

The correct answer is Option (2) → Zoological parks

Option (1) Biosphere reserves — Incorrect. A biosphere reserve is a large protected area where the whole ecosystem is conserved. The species stay in their natural habitat, so this is in situ conservation.

Option (2) Zoological parks — Correct. In ex situ (off-site) conservation, threatened animals and plants are taken out of their natural habitat and cared for in a special setting. A zoological park keeps such animals, and some species that are extinct in the wild survive only there.

Option (3) National park — Incorrect. A national park protects animals and plants where they live naturally. It is a protected area and so a method of in situ conservation.

Option (4) Sanctuaries — Incorrect. A wildlife sanctuary is also a protected natural area. The wild animals are protected in their own habitat, which is in situ conservation.

NCERT Extract:
How Do We Conserve Biodiversity? – …