As you can search and read the definition of a scientific experiment is the process of testing and finding the truth through this scientific method. Thus, all items are considered scientific experiment except for item "c" Ask her coworkers which solution they thick is better.
Explanation: <em>The hypothesis is a prediction, but it involves more than a guess. Most of the time, the hypothesis begins with a question which is then explored through background research. It is only at this point that researchers begin to develop a testable hypothesis.</em>
(Unless you are creating an exploratory study, your hypothesis should always explain what you expect to happen)