A p5-550 with AIX 5.3 is being designed for availability. In addition to providing redundant adapters， which of the following should also be provided？（）
- ARedundant processor pools， UPS， and HACMP
- BRedundant service processors， HACMP， and mirrored AIX drives
- CRedundant processor pools， redundant service processors， and HACMP
- DRedundant power， redundant Virtual I/O Servers， and mirrored AIX drive