Answer: 14 June
Notes: World Blood Donor Day is observed annually on June 14 to raise awareness about the importance of donating safe blood. Initiated by the World Health Organization (WHO) in 2004, the day honors Austrian biologist Karl Landsteiner, born on June 14, 1886. In 2005, the World Health Assembly officially recognized the day. The 2024 theme is "20 years of celebrating giving: thank you, blood donors," marking the 20th anniversary of the observance.
