The correct option for preserving plant genetic material in the `Gene-Bank` is mature seed (dry). This method involves the conservation of fully mature and dry seeds, which are stored at -196° C in liquid nitrogen. Dry seeds have a reduced moisture content, which prevents the formation of ice crystals and fungal growth, ensuring the long-term preservation of the genetic material. This method is efficient because seeds can remain viable for long periods of time without losing genetic integrity. Seedling and meristem preservation (option-1) may be used for short-term conservation but is less suitable for long-term storage. Pre-mature seed (high moisture) (option-3) and ripe fruit (option-4) preservation methods are not commonly used as they are more prone to damage, deterioration, and loss of genetic material.