The correct answer is B. This answer contains a summary of the advantages of cloud storage, which can be developed in the essay as it was stated in the main claim. Also, this answer compares the advantages of cloud storage over traditional data storage; this detail was mentioned in the main claim, and it is restated in the conclusion. None of the other answers contain information restating what was directly said in the claim.
The correct answer is B. Cloud storage is beneficial because it frees you from having to carry a physical storage device and from having to use the same computer to retrieve your data.