State the criteria that a molecule must fulfill to act as a genetic material.

(N/A) molecule must fulfill the following criteria to act as a genetic material:
$(i)$ It should be able to generate its replica (replication).
$(ii)$ It should be chemically and structurally stable.
$(iii)$ It should provide the scope for slow changes (mutation) that are required for evolution.
$(iv)$ It should be able to express itself in the form of 'Mendelian characters'.
If one examines the criteria of base pairing and complementarity,it is evident that both nucleic acids ($DNA$ and $RNA$) have the ability to direct their duplications. Other molecules in the living system,such as proteins,fail to fulfill these criteria.