Question

was first discovered in 1921.​

Answer 1

Answer:

1921 (MCMXXI) was a common year starting on Saturday of the Gregorian calendar and a common year starting on Friday of the Julian calendar, the 1921st year of the Common Era (CE) and Anno Domini (AD) designations, the 921st year of the 2nd millennium, the 21st year of the 20th century, and the 2nd year of the 1920s decade. As of the start of 1921, the Gregorian calendar was 13 days ahead of the Julian calendar, which remained in localized use until 1923.

Explanation:

AND UR ANSWER IS HARMONE INSULIN

MARK BRAINLIEST!