Fact 1: Threatening behavior by predators causes a porcupine to extend its quills. Fact 2: Porcupine quills can be extraordinarily painful. Given the two facts above, answer the question "What can cause predators pain?" with the following options: - animals with backbones - Staying away from porcupine - Ignoring porcupine - pressure on the skin - Befriending porcupine - Threatening behavior towards porcupine - Something with a head, thorax, and abdomen - the body's largest organ
A:
Threatening behavior towards porcupine