American food companies invested heavily in low-carb foods. Then questions arose about the health consequences of the high-protein diets. The market for low-carbs foods dropped significantly. In terms of the innovation process, low-carb foods are an example of

innovation decline
different perceptions
None of the above

innovation decline                  

Explanation:

In terms of the innovation process, low-carb foods are an example of innovation decline. An innovation is said to be on a decline when it does not grow or keep pace with economic growth, rather it experiences a drop in revenue and usage. The drop in the market for low-carb food is an example of innovation decline. For most innovations, the aim is to maintain it at its peak so as to avoid a decline, this is usually achieved by increased value addition, research and development.