Marriage is a stressor because

a. it requires a lifestyle adjustment
b. you are adjusting to another person's daily routine
c. you and your spouse have to decide which roles you will fill
d. all of the above

Marriage is a stressor because d. all of the above

Explanation:

A stressor can be described as something that causes stress or strain to a person. That thing could be physical, mental, situational or environmental. In this case, marriage is a stressor because it requires a lifestyle adjustment, adjusting to another person's daily routine and deciding which new roles to adopt in one's life.

because health skills are tools and strategies and also practical skills are also something you need to learn (like tools and strategies) and put it in reality.