Which of the following sentences correctly uses a semicolon to join independent clauses?

American checkers is called checkers because; the game board is checkered and the British call it draughts after the movement of the pieces.
American checkers was named after the checkered board; The British call the game draughts because of the way the pieces move.
The British game of draughts is played on a checkered board; like American checkers.
The British game of draughts was named after the movement of pieces on a checkered board; Americans call the game checkers because of the checkered board.

The British game of draughts was named after the movement of pieces on a checkered board; Americans call the game checkers because of the checkered board.