The concept of Intelligence Quotient was devised/coined by.....

Correct option is C

William Stern coined/devised the concept of Intelligence Quotient (IQ) in 1912.
Basic information about the topic: Intelligence Quotient (IQ) is a standardized measure designed to assess human cognitive abilities and intellectual potential relative to age norms.
Information Booster: Explanation of the correct answer in pointers in detail
· Origin of the Term: The concept and term Intelligence Quotient (IQ) were originally introduced and coined by the German psychologist William Stern in 1912.
· Original Formula by Stern: Stern defined IQ as the ratio of a person's mental age to their chronological (actual) age:

· Refinement by Lewis Terman: While Stern devised the ratio formula, it was American psychologist Lewis Terman of Stanford University who later multiplied this quotient by 100 (giving the modern formula: IQ = MA/CA x 100 while developing the Stanford-Binet Intelligence Scale in 1916.
· Contribution to Psychometrics: Stern's quotient provided a groundbreaking standardized method to compare cognitive development across children of varying biological ages.
Additional Knowledge:
Explanation of the other options apart from the correct statements
· William James:
· Why it is not correct: William James is widely recognized as the "Father of American Psychology" and a pioneer of the psychological school of Functionalism.
· He authored the influential text The Principles of Psychology (1890) and studied consciousness, pragmatism, and emotion, but he did not develop or coin intelligence quotient metrics.
· William Wundt (Wilhelm Wundt):
· Why it is not correct: Wilhelm Wundt is celebrated as the "Father of Experimental Psychology" for establishing the world's first formal psychology laboratory in Leipzig, Germany (1879).
· His work focused primarily on Structuralism, introspection, and sensory perception, rather than mental testing or intelligence measurement.
· William Blake:
· Why it is not correct: William Blake was an iconic English Romantic painter, poet, and printmaker from the late 18th and early 19th centuries (famous for works like Songs of Innocence and Experience).
· He had no connection to educational psychology, psychometrics, or cognitive testing.