Match the ex situ conservation method with its description.
| Column I | Column II |
|---|---|
| (a) Zoological parks | (i) Preservation of gametes of threatened species in viable conditions |
| (b) Botanical gardens | (ii) Have collections of living plants for reference |
| (c) Cryopreservation | (iii) Where wild animals are kept in protected environments |
| (d) Seed banks | (iv) A method to store seeds for long periods |