Which choice shows the best way to join two independent clauses with a semicolon?

My brother is a computer whiz; I can barely type my name.

My brother knows a lot about computers; more than I do.

While my brother plays on his computer; I like to paint.

My brother is a computer whiz; but I am not.

The choice that shows the best way to join two independent clauses with a semicolon is the first choice:

My brother is a computer whiz; I can barely type my name.

The other possible choice would be the second sentence, but since more than I do is not an independent clause, this cannot be the correct answer.