Which of the following can negatively impact a consumer's credit score?

High credit utilization ratios can negatively impact a consumer's credit score because they represent the amount of available credit being used in relation to the total credit limit across all accounts. A high utilization ratio suggests that a consumer may be overly reliant on credit, which can be seen as a risk by lenders. In general, it is advisable to keep credit utilization below 30% of the total credit limit. When the ratio exceeds this threshold, it may indicate financial strain or poor credit management, which can lead to a decrease in credit scores.

This is in contrast to paying bills on time, which is a positive behavior that contributes to a higher credit score. Closed accounts can also have varying impacts on credit scores depending on the circumstances surrounding the closure, such as whether they were closed in good standing or resulted from missed payments. Lastly, while having multiple credit inquiries can impact a score, particularly if they are for new credit applications over a short period, it's often less significant than the effect of high credit utilization. Therefore, high credit utilization ratios are a clear indicator of potential credit risk and can have a direct negative consequence on a consumer's credit score.