[Solved] According to __________________ theory, members of a couple in a long-term relationship should prefer to spend time with each other rather than people they don't know very well. A) behavioral interaction B) socioemotional selectivity C) need complementarity D) social exchange Isopropyl Alcohol: A colorless, flammable chemical compound with a strong odor, commonly used as a disinfectant, solvent, and antiseptic. Specimen Slide: A thin slice of material, such as tissue, mounted on a slide for examination under a microscope. Microscope: An instrument used to view objects that are too small to be seen by the naked eye, magnifying tiny details for study or observation. Substage: A division or phase within a larger stage or process, often indicating a specific part of a broader developmental or operational sequence.