The periodic law, as we know it today, owes its development to two chemists.
(i) John Newlands (ii) Dmitri `I`. Mendeleev
(iii) `J`.Lothar Meyer (iv) `J.W`. Dobereiner

Options

A. Rutherford and Moseley
B. Alexander newlands and dobereiner
C. Dmitri mendeleev and Lothar Meyer
D. De broglie and Neil bohr.

Answer

To solve the question regarding the development of the periodic law and the two chemists responsible for it, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Question**: The question asks for the two chemists who contributed to the development of the periodic law as we know it today.

2. **Identify the Chemists**: The options provided are:
- (i) John Newlands
- (ii) Dmitri I. Mendeleev
- (iii) J. Lothar Meyer
- (iv) J.W. Dobereiner

3. **Recall Contributions**:
- **John Newlands**: Proposed the Law of Octaves, which was an early attempt to classify elements based on their properties but is not the basis of the modern periodic law.
- **Dmitri I. Mendeleev**: Developed the first widely recognized periodic table, arranging elements by increasing atomic weight and grouping them by similar properties.
- **J. Lothar Meyer**: Independently created a periodic table similar to Mendeleev's, also based on atomic weights and properties.
- **J.W. Dobereiner**: Known for the triads concept, which grouped elements with similar properties but did not contribute directly to the periodic law.

4. **Select the Correct Chemists**: The two chemists who significantly contributed to the periodic law are:
- Dmitri I. Mendeleev
- J. Lothar Meyer

5. **Final Answer**: The correct option is (iii) Mendeleev and Lothar Meyer.