(a) The plant X is Bryophyllum.
(b) The entities, Y, present on the leaves of X are known as buds.
(c) Other than X, Begonia can also be reproduced by its leaves.
(d) Money plant can be propagated from its broken stem similar to plant X.
(e) Buds are present in the dry stems of the old grass lying in the fields. These buds get activated after a spell of shower, and start producing new grasses.