Ans.
Growing of a plant from other plant, such as from seeds, cutting, or tubers is known as plant propagation. It can be divided into sexual propagation and asexual propagation. Sexual propagation involves development of new plants from spores and seeds.
Asexual reproduction involves development of new plants from vegetative plant structures, such as stem, nodes, or bulbs. It is an inexpensive and easy method to get new plants from old plants.
Thus, the correct word to be filled in the blank is option). 'propagation.'