How did Charles Spearman conceptualize intelligence

A)  It is made up of a "core factor" common to all intellectual abilities. 
B)  It is seen only in certain "school-type" problems. 
C)  It can change from time to time. 
D)  It is a series of unrelated factors.

Charles Spearman

A psychologist known for his pioneering work in statistics and intelligence, specifically for his development of factor analysis and the concept of a general intelligence factor, "g".

Intelligence

The ability to acquire, understand, and apply knowledge and skills, and to adapt to new situations.