The concept of Intelligence Quotient or IQ was developed by -

Question

Accepted Answer

The concept of Intelligence Quotient, or IQ, was developed by William Stern, which is why Option 3 is the correct answer. Here is a detailed explanation supporting this choice:

1. **William Stern (Option 3):** William Stern, a German psychologist, introduced the term "Intelligence Quotient" (IQ) in 1912. He proposed the idea of dividing a person's mental age by their chronological age and then multiplying the result by 100 to obtain the IQ score. This formula provided a standardized way to measure intelligence, allowing for comparisons across different age groups. Stern's contribution was pivotal in the development of intelligence testing, making Option 3 the correct answer.

2. **Why the other options are incorrect:**

- **Galton (Option 1):** Sir Francis Galton was a pioneer in the study of human intelligence and is known for his work on eugenics and the concept of correlation. While he laid the groundwork for the study of individual differences in intelligence, he did not develop the concept of IQ. His focus was more on the hereditary aspects of intelligence rather than quantifying it through a quotient.

- **Binet (Option 2):** Alfred Binet, a French psychologist, is credited with developing the first practical intelligence test, known as the Binet-Simon scale, in the early 20th century. Although Binet's work was crucial in the field of intelligence testing, he did not create the IQ concept. His tests were designed to identify children who needed educational assistance, and he was cautious about using his tests to label individuals with a fixed measure of intelligence.

- **Terman (Option 4):** Lewis Terman, an American psychologist, is known for revising the Binet-Simon scale into what became known as the Stanford-Binet Intelligence Scales. Terman's work was significant in popularizing intelligence testing in the United States, and he played a key role in the widespread adoption of IQ testing. However, he did not originate the IQ concept itself; he built upon Stern's idea and adapted it for broader use.

In conclusion, while each of these individuals made significant contributions to the field of intelligence research, it was William Stern who specifically developed the concept of the Intelligence Quotient, making Option 3 the correct answer.