The correct answer is A. The decision to accept or reject a VaR model based on backtesting results at the two-tailed 95% confidence level is less reliable using a 99% VaR model than using a 95% VaR model. This is because using a 95% VaR confidence level creates a narrower nonrejection region than using a 99% VaR confidence level by allowing a greater number of exceptions to be generated. This increases the power of the backtesting process and makes for a more reliable test than using a 99% confidence level. The explanation highlights the importance of understanding the difference between the VaR parameter for confidence (95% vs. 99%) and the validation procedure confidence level (95%), and how they interact with one another in the context of backtesting a VaR model.