challenge: What actions did Chadae of Goguryeo take in the third year of his reign to consolidate power?
  
  A. He appointed his brothers to key government positions and strengthened trade relationships with neighboring kingdoms.
  B. He ordered the deaths of Taejo's two sons, forced one of his brothers to commit suicide, and persecuted his youngest brother Baekgo.
  C. He reformed the kingdom's administrative system and promoted education and the arts.
  D. He launched a series of military campaigns to expand Goguryeo's borders and increased taxes on the population.
  Answer: 