The scientist who propounded the theory of inheritance of acquired characters via use and disuse was

Step 1: Analyze the question The question asks who proposed the theory of inheritance of acquired characters through use and disuse.

Step 2: Explain the concept Lamarckism (1809) says that:

• Organs that are used often become bigger and stronger, while organs that are not used weaken and disappear (use and disuse).
• These changes, acquired during an organism's lifetime, are passed on to its offspring (inheritance of acquired characters).

Classic example: Lamarck suggested that giraffes stretched their necks to reach high leaves. Their necks lengthened, and the longer necks were passed on to their offspring.

Step 3: Check each option

• A. August Weismann: He disproved Lamarck's idea by cutting off the tails of mice over many generations. Their offspring were still born with tails. He proposed the germ plasm theory.
• B. Charles Darwin: He proposed natural selection, not use and disuse as the main mechanism.
• C. Gregor Mendel: He is the father of genetics and worked on the laws of inheritance in pea plants.
• D. Jean Lamarck: He proposed use and disuse and the inheritance of acquired characters. This matches the question.
• E. Thomas Morgan: He worked on chromosomes and linkage in Drosophila (fruit flies).

Step 4: Answer The correct answer is **D.

Exam tip: Link the names to their ideas:

• Lamarck = "Lazy organs fade, busy organs grow" (use and disuse)
• Darwin = Dsurvival of the fittest (natural selection)
• Mendel = Math of peas (heredity)
• Weismann = Wipe off tails (disproved Lamarck)