In 1994, researchers herrnstein and murray published a controversial book entitled in which they implied that people from lower socioeconomic classes are poor because they are less intelligent.

In 1994, psychologist Richard J. Herrnstein and political scientist Charles Murray published a controversial book entitled  "The Bell Curve: Intelligence and Class Structure in American Life", in which the  authors argue that human intelligence is substantially influenced by both inherited and environmental factors. The book's title comes from the bell-shaped normal distribution of intelligence quotient (IQ) scores in a population. 

N 1994, psychologist Richard J. Herrnstein and political scientist Charles Murray published a controversial book entitled  "The Bell Curve:
 Intelligence and Class Structure in American Life", in which the authors argue that human intelligence is substantially influenced by both inherited and environmental factors. The book's title comes from the bell-shaped normal distribution of intelligence quotient (IQ) scores in a population

Explanation: Bell Curve: Intelligence and class Structure in American Life may be a 1994 book by scientist Richard J. Herrnstein and social scientist Charles Murray, during which the authors argue that human intelligence is well influenced by each transmissible and environmental factors which it's a higher predictor of the many personal dynamics, together with monetary financial gain, job performance, birth out of marital status, and involvement in crime than are somebody's parental socioeconomic standing.

The answer is b. increased blood flow reduces nerve sensitivity