Attempts to identify a set of traits that distinguish leaders from​ non-leaders failed because​ __________.
a. traits associated with leadership are distributed equally throughout the population
b. parental guidance and​ early-life experiences were more likely to determine whether a person later became a leader
c. traits associated with leadership are​ culture-specific
d. these attempts ignored the interactions between leaders and their group members
e. leaders are​ made, not born