Acquired characteristics of Lamarck are not inherited and have an evolutionary value. Who gave this statement?

The correct option is Weismann.

Lamarckism, or the theory of inheritance of acquired characters proposed by Jean-Baptiste Lamarck, suggested that changes or characteristics acquired by an organism during its lifetime in response to the environment could be passed on to its offspring, thereby driving evolution.

This idea was famously disproved by the German biologist August Weismann through his germ plasm theory. Weismann conducted experiments where he cut off the tails of mice for many successive generations and observed that the offspring were always born with normal, full-length tails. Based on this, he concluded that changes in the somatoplasm (body cells) do not affect the germplasm (reproductive cells) and are therefore not transmitted to the next generation.

Thus, Weismann established that the acquired characteristics of Lamarck are not inherited and do not possess evolutionary value because only variations present in the germ cells can be inherited and contribute to evolution.