pH scale was introduced by :

Options

A. Arrhenius
B. Sorensen
C. Lewis
D. Lowry

Explanation

To solve the question regarding who introduced the pH scale, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Concept**: The question asks about the introduction of the pH scale, which is a measure of acidity or alkalinity of a solution.

2. **Historical Context**: The pH scale was first introduced in the early 20th century. It's important to note the year and the context in which it was developed.

3. **Research the Chemist**: The pH scale was introduced by a Danish chemist. We need to find out who this chemist is.

4. **Name the Chemist**: The chemist who introduced the pH scale in 1909 was Søren Petter Loris Sørensen. He worked at the Carlsberg Laboratory.

5. **Revisions and Modernization**: Sørensen later revised the pH scale in 1924, accommodating various definitions and measurements related to acidity and alkalinity.

6. **Conclusion**: Based on the information gathered, the correct answer to the question is that the pH scale was introduced by Søren Petter Loris Sørensen.

### Final Answer:
The pH scale was introduced by Søren Petter Loris Sørensen.