The answer is C. This is because but is being used as a conjunction separating independent clauses in the other answers. You can remove but from A, B, and D, and you are left with 2 simple sentences.
I hope this helps!!!
Answer: A computer, A modem and telephone line (if you are using dial up access) A data line of some sort (if you are not using dial up access), Strong wifi connection, An Internet browser (software) and software to connect you to the ISP, An account with an Internet Service Provider (ISP) Souvenirs.
Wrote :D is the correct so B
Most available. Hope this helped.