Answer:
i think it is c
I am so sorry if the answer is wrong
Answer: but
Explanation:
In 1863, President Abraham Lincoln designated the last Thursday in November as a national holiday of Thanksgiving ....... in 1939, President Franklin Roosevelt decreed that the holiday should always be celebrated on the fourth Thursday of the month.
Out of the options given, the answer is "but". This is the right answer as it'll be used to link both sentences regarding the two activities of the President's together.
The other options such as "for example", "therefore" and "so" when used doesn't make the sentence correct.
900Boxer Rebellion in ChinaItaly's King Umberto I AssassinatedKodak Introduces $1 Brownie CamerasMax Planck Formulates Quantum TheorySigmund Freud Publishes The Interpretation of Dreams
1910Boy Scouts Established in U.S.Halley's Comet Makes an AppearanceThe Tango Catches On
1920Bubonic Plague in IndiaFirst Commercial Radio Broadcast AiredHarlem Renaissance BeginsLeague of Nations EstablishedProhibition Begins in the U.S.Pancho Villa RetiresWomen Granted the Right to Vote in U.S.
1930Gandhi's Salt MarchPluto DiscoveredStalin Begins Collectivizing Agriculture in the U.S.S.R.
Hoped this helped