Which was the biggest land dinosaur ?

Options

A. Protoceratops
B. Camptosaurus
C. Tyrannosaurus rex
D. Ichthyosaur

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the biggest land dinosaur among the given options: Protoceratops, Camptosaurus, Tyrannosaurus rex, and Ichthyosaur.

2. **Identifying the Largest Dinosaur**: The largest dinosaur ever known is Argentinosaurus, which is not listed in the options. However, we need to focus on the options provided.

3. **Evaluating the Options**:
- **Protoceratops**: A small ceratopsian dinosaur, not known for large size.
- **Camptosaurus**: A medium-sized herbivorous dinosaur, also not among the largest.
- **Tyrannosaurus rex**: Known as T. rex, it is one of the largest carnivorous dinosaurs and is often considered one of the largest land dinosaurs.
- **Ichthyosaur**: This is not a dinosaur; it is a marine reptile.

4. **Conclusion**: Among the options provided, the Tyrannosaurus rex is the largest land dinosaur. Therefore, the correct answer is option C: Tyrannosaurus rex.

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