Major concern of curriculum is:

The fundamental purpose of any curriculum is to facilitate learning and development in individuals. This learning is ultimately reflected in observable or measurable changes.

• A: Change in individual's behavior is the major concern. This encompasses cognitive changes (gaining knowledge), psychomotor changes (developing skills), and affective changes (modifying attitudes, values, and beliefs). Curriculum aims to equip learners with new ways of thinking, acting, and feeling.
• B: Preparation for service might be a specific goal for vocational or professional curricula, but it's not the overarching concern for all educational programs.
• C: Personal satisfaction is a positive outcome of successful learning but not the primary objective of curriculum design itself.

Thus, the most comprehensive and accurate answer is that curriculum aims to bring about desired changes in an individual's behavior.