The scientist who suspected the presence of some growth substances was

Options

A. Linnaeus
B. Mendel
C. Charles Darwin
D. Robert Brown

Answer

To answer the question regarding which scientist suspected the presence of growth substances in plants, we can follow these steps:

### Step 1: Understand the Question
The question asks for the scientist who suspected the presence of growth substances, which are also known as phytohormones or growth hormones in plants.

### Step 2: Analyze the Options
The options provided are:
- Linnaeus
- Mendel
- Charles Darwin
- Robert Brown

### Step 3: Recall Contributions of Each Scientist
- **Linnaeus**: Known for developing the system of naming organisms (binomial nomenclature).
- **Mendel**: Known for his work in genetics and the laws of inheritance.
- **Robert Brown**: Recognized for discovering the nucleus in cells.
- **Charles Darwin**: Known for his theory of evolution and also conducted experiments related to plant growth and phototropism, which led him to suspect the presence of growth substances.

### Step 4: Identify the Correct Scientist
Among the options, Charles Darwin is the one who suspected the presence of growth substances in plants, as he conducted experiments that indicated the influence of certain substances on plant growth.

### Step 5: Conclude the Answer
The correct answer to the question is **Charles Darwin**.

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