The correct option is C Weismann
In 1893, a German Biologist by the name August Weismann, put forth the theory of germplasm, in which he suggested that environmental factors affect only the somatic cells and not the germ (sex) cells. Thus, he explained that acquired characters would be lost with the death of that particular organism. Weismann proved this by cutting off the tails of mice for several generations and allowing them to breed. The result was that tailless mice were never born. This theory strongly disproved Lamarckism.