The atomic theory of matter was proposed by :

Options

A. John Kennedy
B. Lavoisier
C. Proust
D. John Dalton

Answer

To solve the question regarding who proposed the atomic theory of matter, we can follow these steps:

### Step 1: Understand the Question
The question asks for the scientist who proposed the atomic theory of matter. The atomic theory explains that matter is composed of small, indivisible particles called atoms.

### Step 2: Analyze the Options
We have four options to consider:
- A) John Kennedy
- B) Lavoisier
- C) Proust
- D) John Dalton

### Step 3: Recall Historical Contributions
- **John Kennedy**: Not known for contributions to atomic theory.
- **Lavoisier**: Known for the law of conservation of mass, not specifically for atomic theory.
- **Proust**: Known for the law of definite proportions, but not the atomic theory itself.
- **John Dalton**: Proposed the first comprehensive atomic theory in the early 19th century, stating that all matter is made up of atoms.

### Step 4: Identify the Correct Answer
Based on the analysis, the correct answer is **D) John Dalton**. He is credited with formulating the atomic theory of matter.

### Final Answer
The atomic theory of matter was proposed by **John Dalton**.

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