When he heard that turnover was increasing, the human resource manager immediately told the president that salaries would have to be ralsed. Unfortunately, low pay wasn't the cause of the turnover. Which decision making error did the manager commit?

a$)$ He treated sunk costs improperly

b$)$ He defined the problem in terms of a solution

c$)$ He escalated commitment

d$)$ He exhibited the knew$-$it$-$all$-$along effect

e$)$ He revealed a confirmation bias