Final answer:
The policy not undertaken by the NIRA was the agreement among industries to reinvest profits into their firms. The NIRA did include setting prices, production levels, and the right of workers to form unions.
Step-by-step explanation:
The question asks which policy was not undertaken by the National Industrial Recovery Act (NIRA).
The NIRA included several policies, such as agreement among industries to set prices, set production levels, and the recognition of the right of workers to form unions.
These efforts were part of the National Recovery Administration (NRA), which created codes for industries to regulate wages, prices, and production.
However, an agreement among industries to reinvest profits into their firms was not a policy of the NIRA. Therefore, the correct answer is B. agreement among industries to reinvest profits into their firms.