Final answer:
The secretary of HUD has 100 days to file a charge or dismissal after an investigation following the filing of a complaint.
Step-by-step explanation:
The secretary of HUD (Department of Housing and Urban Development) is responsible for handling complaints and investigations related to housing discrimination. The timeframe for the secretary to file a charge or dismissal after an investigation following the filing of a complaint is within 100 days (d) according to the Fair Housing Act. This gives the secretary enough time to thoroughly investigate the complaint and make a decision based on the findings.