Based on the clue '1 of the 3 cs in the geological period mnemonic ca...', what is the answer?

Based on the clue '1 of the 3 african countries that are still kingdo...', what is the answer? Based on the clue '1 of the 3 alien races mark lenard portrayed in th...', what is the answer? Based on the clue '1 of the 3 british actresses who married laurence ...', what is the answer? What is associated with: 1 of the 3 civil rights workers murdered near philadelphia mississippi in june 1964? Based on the clue '1 of the 3 fireproof companions in daniel 3', what is the answer? What is associated with: 1 of the 3 former soviet satellites that joined nato in 1999? Based on the clue '1 of the 3 french cities to host the winter olympi...', what is the answer? Based on the clue '1 of the 3 heavyweight boxing champs to fit this c...', what is the answer?