Which statement is true when continuously deploying using a DevOps model?

When continuously deploying using a DevOps model, it is true that it lessens the severity and frequency of release failures. This is primarily because the continuous deployment process encourages smaller, more frequent releases rather than infrequent, large updates. By deploying changes incrementally, teams can integrate and validate code more often, allowing for early detection and resolution of issues. This reduces the risk associated with each deployment, making failures less severe, and ensures that teams can respond more rapidly to any problems that do arise.

In addition, continuous integration practices, which are a critical part of the DevOps model, help ensure that code is tested automatically before deployment. This practice minimizes the likelihood of defects making it into production, thereby lowering both the severity of failures when they do occur and the frequency with which those failures take place.

The other choices are not accurate representations of the benefits or nature of continuous deployment in a DevOps context. For instance, increasing transaction costs does not align with the efficiencies gained in DevOps practices, while the statement about ensuring immediate availability overlooks potential testing and release impacts. Furthermore, the idea that extensive manual testing is required contradicts the automation goals at the heart of the DevOps philosophy.