Darwin concluded from his observations of nature and readings that:

• A. acquired traits are inherited by offspring
• B. all individuals in a population are identical
• C. species evolve over time through natural selection
• D. organisms do not change in response to their environment

Answer: (C)

Verified step by step guidance

1. Understand the context of the question: Charles Darwin's theory of evolution is based on the concept of natural selection, which explains how species adapt and evolve over time due to environmental pressures and genetic variation.
2. Eliminate incorrect options: Darwin did not propose that acquired traits are inherited by offspring. This idea was part of Lamarck's theory, which has been largely discredited.
3. Analyze the statement 'all individuals in a population are identical': This is incorrect because Darwin observed variation among individuals in a population, which is a key factor in natural selection.
4. Evaluate the statement 'organisms do not change in response to their environment': This is also incorrect because natural selection is driven by environmental pressures that favor certain traits over others, leading to changes in populations over generations.
5. Conclude that the correct answer is 'species evolve over time through natural selection,' as this aligns with Darwin's observations and the principles of his theory of evolution.