The correct answer is C, 'Trade fixed expenses for variable expenses'. This is one of the key advantages of AWS Cloud computing. With cloud computing, businesses can avoid the large upfront costs and long-term commitments associated with purchasing and maintaining on-premises hardware and software. Instead, they pay only for the computing resources they use, which can be scaled up or down as needed. This allows businesses to be more flexible and responsive to changing demands, while also reducing their overall IT costs.