How can we preserve medicinal plants​

Explanation:

Conservation of medicinal plants can be accomplished by the ex-situ i.e. outside natural habitat by cultivating and maintaining plants in botanic gardens, parks, other suitable sites, and through long term preservation of plant propagules in gene banks (seed bank, pollen bank, DNA libraries, etc.)

Explanation:

d) all choices are correct

c) troops march forward in close formation against newer, more accurate weapons