Final answer:
A depression rebound taking 16-30 seconds on the edema scale would most likely be classified as 2+.
Step-by-step explanation:
On the edema scale, a depression rebound taking 16-30 seconds would most likely be classified as 2+, according to the options given in the question. In this context, the edema scale is measuring the time it takes for a depression (indentation or swelling) to rebound or return to its original state. A depression rebound that takes 16-30 seconds would fall under the 2+ category in terms of severity or duration.