Final answer:
Savoring pleasures, gratitude, engagement, and contribution can all increase happiness.
Step-by-step explanation:
All of the options listed can increase happiness. Savoring pleasures is about consciously enjoying and appreciating positive experiences, which can bring happiness. Gratitude involves acknowledging and expressing appreciation for the positive aspects of life, which can also contribute to happiness. Engagement refers to being fully absorbed and immersed in activities that one finds meaningful and enjoyable, leading to happiness. Contribution involves helping and giving to others, which has been shown to boost happiness. Therefore, all of these options can increase happiness.