Discovery of which of the following hormones is an example of serendipity?a- Auxinsb- Gibberellinsc- Cytokininsd- Ethylenee- Abscisic acid

Interestingly, the discovery of each of the five major groups of PGRs have been accidental. All this started with the observation of Charles Darwin and his son Francis Darwin when they observed that the coleoptiles of canary grass responded to unilateral illumination by growing towards the light source (phototropism).