Which is a major concept included in lamarck's evolutionary hypothesis?

The correct answer is - Body organs or structure can change according to the actions or use of the organ by the organism.

Explanation:

Lamarck presented the evolutionary hypothesis in which the theory of inheritance of acquired characteristics was the prime concept presented in 1801. According to this if an individual organism changes or alters the characteristics during life in order to change to its atmosphere and actions or use of organs included in this as well.

Body structure or the organ can change them as per the use and characteristics that are adapted according to the action to survive.

Thus, the correct answer is - Body organs or structure can change according to the actions or use of the organ by an organism.