Who would have been most enthusiastic about the value of a single intelligence test score as an index of an individual's mental capacities?

A. Thurstone

B. Spearman

C. Gardner

D. Sternberg

B. Spearman

Explanation:

Charles Spearman was a psychologist who proposed a theory of intelligence. According to him, there's a general factor (the g factor) that can be defined as the overall mental capacity of a person and that it's shown when this person performs cognitive tasks.

According to him, there are no different types of intelligence but just a general factor that determines the "intelligence" of a person and, by determining the value of this factor we could determine one person mental capacities.

Unlike the other authors given in the option, he is the only one who thinks there's a single factor behind intelligence measures (Thurstone believed there were different mental abilities, Gardner proposed the theory of multiple intelligences and Sternberg thought that there were 3 types of intelligence)

Therefore, we can conclude that Spearman would have been the most enthusiastic about the value of a single intelligence test score as an index of an individual's mental capacities.