In 1871, Charles Darwin described in his book "The Descent of Man" that

Options

A. monkeys and apes had a common ancestor
B. apes and man had a common ancestor
C. prosimians and simians had common ancestor
D. monkey, apes and men had common ancestor

Answer

**Step-by-Step Solution:**

1. **Understanding the Context**: In 1871, Charles Darwin published "The Descent of Man," which discussed human evolution and the relationships between humans and other primates.

2. **Identifying the Main Idea**: The book emphasized that humans share a common ancestry with other primates, particularly monkeys and apes.

3. **Evaluating the Options**:
- **Option 1**: Monkeys and apes had a common ancestor.
- This is partially correct but does not include humans.
- **Option 2**: Apes and man had a common ancestor.
- This is also partially correct but does not include monkeys.
- **Option 3**: Spruce, simians, and simians had a common ancestor.
- This option is irrelevant to Darwin's discussion.
- **Option 4**: Monkeys, apes, and man had a common ancestor.
- This option encompasses the idea that all three share a common ancestor, which aligns with Darwin's assertions.

4. **Conclusion**: Based on Darwin's descriptions in "The Descent of Man," the correct answer is that monkeys, apes, and man had a common ancestor.

**Final Answer**: The correct option is **fourth option**: Monkeys, apes, and man had a common ancestor.

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