Which sentence is punctuated correctly?

Question

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Although, Davis had to work on his geography assignment; he offered to help Dana with her household chores.
Although Davis had to work on his geography assignment, he offered to help Dana with her household chores.
Although, Davis had to attend work on his geography assignment, he offered to help Dana, with her household chores.
Although Davis had to work on his geography assignment; he offered to help Dana with her household chores.

Answer 1

The correctly punctuated sentence is:

Although Davis had to work on his geography assignment, he offered to help Dana with her household chores.