Which is an example of a conceptual definition of a dependent variable in a study evaluating the ...

Which is an example of a conceptual definition of a dependent variable in a study evaluating the effects of home nursing on coping among patients with chronic illness?
 
  a. Coping is a set of actions and strategies used by individuals to reduce the stressors associated with chronic disease management.
  b. Coping skills were measured using a five-point Likert scale with higher scores indicating higher coping skills.
  c. Home nursing can include registered nurse and nursing assistant management of treatments provided at home.
  d. Home nursing was measured in the number of hours per week and the number of hours per day of in-home care.