Which of the following mechanisms is NOT one used in Synectics?

In the context of Synectics, which is a creative problem-solving technique that encourages thinking outside the box, the correct answer highlights that "Biological analogy" is not a recognized mechanism used within this framework.

Synectics employs various types of analogies to connect different concepts in innovative ways, and the other options are all legitimate mechanisms. Direct analogy draws comparisons between different areas or fields to inspire new ideas. Personal analogy encourages individuals to empathize with the elements of a problem by imagining themselves in that situation. Symbolic analogy uses symbols or metaphors to generate insight and foster creativity.

Since "Biological analogy" does not fit within these established mechanisms of Synectics, it stands out as the incorrect choice in this context. Synectics focuses primarily on the metaphoric and analogical connections that can yield creative outcomes, which is why the other options are useful tools in the process.