How do you achieve usefulness in design?By combining utility (whether the system offers the right features to solve a problem) and usability (whether people are able to use those features)1By combining usefulness, explicability, simplicity, scalability, and addictiveness2By combining learnability, efficiency, memorability, error tolerance, and satisfaction3None of the above4ReportConfirm

The question seems to be asking how to achieve usefulness in design. Here are the options provided:

1. By combining utility (whether the system offers the right features to solve a problem) and usability (whether people are able to use those features)
2. By combining usefulness, explicability, simplicity, scalability, and addictiveness
3. By combining learnability, efficiency, memorability, error tolerance, and satisfaction
4. None of the above

To achieve usefulness in design, it is generally accepted that a combination of utility and usability is key. This means that the system should offer the right features to solve a problem (utility), and people should be able to use those features (usability). Therefore, option 1 seems to be the most accurate answer.

However, the other options also have merit. For example, a design that is simple, scalable, and addictive can also be considered useful. Similarly, a design that is easy to learn, efficient, memorable, tolerant of errors, and satisfying can also be useful.

Ultimately, the usefulness of a design can depend on a variety of factors, and different people may have different opinions on what makes a design useful. Therefore, while option 1 seems to be the most generally accepted answer, the other options could also be considered correct depending on one's perspective.