Human Capital Refers to Which of the Following

Human capital refers to which of the following?

A) the quantity of goods and services that can be produced by one worker or by one hour of work
B) the accumulated knowledge and skills workers acquire from education and training or from their life experiences
C) manufactured goods that are used to produce other goods and services
D) physical equipment that is made by human labourers, not machines
E) the number of workers that apply for a specific job or can be hired on short notice