Choice "D" is correct. A "sketchy" design structure would have higher risk than well defined structure. A new technology and a sketchy design structure would present the highest risk These issues would need to be considered as part of the risk management component of COBIT.
Choice "c" is incorrect. A current technology is always going to have a lower, not a higher, risk than a new technology. The design structure could then almost be considered to be irrelevant, because the choice is already incorrect.
Choice "b" is incorrect. A current technology is always going to have a lower, not a higher, risk than a new technology. The design structure could then almost be considered to be irrelevant, because the choice is already incorrect.
Choice "a" is incorrect. A new technology is always going to have a higher, not a lower, risk than a current technology. However, a well-defined structure can be assumed to lower the risk.