Which of these sentences is punctuated correctly? (Illuminate)

Question

Although the rafters felt nervous about the rapids; the guide believed that it was safe; so they were reassured.

Although the rafters felt nervous about the rapids the guide believed that they were safe so they were reassured.

Although the rafters felt nervous about the rapids; the guide believed that they were safe, so they were reassured.

Although the rafters felt nervous about the rapids, the guide believed that they were safe, so they were reassured.

Answer 1

The correctly punctuated sentence is:

Although the rafters felt nervous about the rapids, the guide believed that they were safe, so they were reassured.