According to Hugo de Vries, the mechanism of evolution is?

The correct option is A

Saltation

The correct option is A.

Explanation of correct option:

1. The development of newer types of organisms from pre-existing ones is called 'evolution.'
2. Based on his work on evening primrose, Hugo de Vries proposed the idea of mutations.
3. According to him, mutations are random and directionless.
4. He also stated that mutation creates speciation.
5. Hugo de Vries believed that mutation caused evolution and called it saltation (single-step large mutation).

Explanation of incorrect option:

Option B:

According to Hugo de Vries, mutations are non-minor variations that lead to evolution.

Option C:

Hugo de Vries didn't believe that phenotypic variations cause evolution.

Option D:

Hugo de Vries called mutations the basis of evolution, and it is a single-step process.

Final answer: According to Hugo de Vries, the mechanism of evolution is saltation.