To prove theory of mutation, Hugo de Vries used _________ plant.

The correct answer is Option (2) → Evening primrose

Option (1) Snap dragon or Antirrhinum — Incorrect. The snapdragon is the textbook example of incomplete dominance in flower colour.

Option (2) Evening primrose — Correct. Hugo de Vries, working on the evening primrose, brought forth the idea of mutations: large, sudden variations that cause speciation. He called this saltation.

Option (3) Dog flower — Incorrect. Dog flower is another name for the snapdragon, so it fails for the same reason.

Option (4) Pisum sativum — Incorrect. The garden pea is the plant Mendel used for his laws of inheritance.

NCERT Extract:
Mechanism of Evolution – “… Even though Mendel had talked of inheritable ‘factors’ influencing phenotype, Darwin either ignored these observations or kept silence. In the first decade of twentieth century, Hugo deVries based on his work on evening primrose brought forth the idea of mutations – large difference arising suddenly in a population. He believed that it is mutation which causes evolution and not the minor variations (heritable) that Darwin talked about.”