Hugo de Vries proposed “mutation theory of evolution” while working on

The correct option is A Oenothera lamarckiana
Hugo de Vries believed that single step large mutations (saltations) were responsible for the formation of the new species in a single generation. He worked on Oenothera lamarckiana or evening primrose and proposed the mutation theory of evolution which was later published in his book “The Mutation Theory”.



He observed that this plant occasionally has offspring with significant phenotypic differences such as large leaves and flowers, and some plants with oblong leaves. These offspring could pass on the mutations to subsequent generations without blending the variant for many generations.

Mendel conducted hybridisation experiments on Pisum sativum (garden pea) for a period of seven years between 1856-1863 and proposed the laws of inheritance.

Morgan, based on his experiments conducted on Drosophila melanogaster, gave experimental verification of the chromosomal theory of inheritance and discovered the concept of linkage. The close association of genes on the chromosomes is called linkage.

Weismann proposed the theory of “Continuity of germplasm”, stating that variations in germ cells are only inherited. He conducted an experiment on rats by amputating their tails and found that on breeding these tailless rats, none of the progeny were born without tails.