Final answer:
According to the two-factor theory of emotion, passionate love can be facilitated by physical arousal that is cognitively labeled as love.
Step-by-step explanation:
The two-factor theory of emotion posits that emotions are the result of both physiological arousal and cognitive labeling of that arousal. Therefore, when considering which factor can facilitate passionate love, we should look for an option that involves physiological arousal followed by a cognitive appraisal. The correct answer is physical arousal. According to the two-factor theory, passionate love can be facilitated by physical arousal, which is then cognitively labeled as love in the right context. This theory emphasizes the importance of both physical and cognitive elements in the experience of emotions such as passionate love.