In biology, the different areas of study are connected and overlap in various ways, with concepts that cut across all disciplines. Which pair of crosscutting concepts are BEST exemplified when birds fly south when winter comes to the United States, and north when spring arrives? a. stability and change; scale, proportion, and quantity b. systems and system models; scale, proportion, and quantity c. patterns; cause and effect d. energy and matter: flows, cycles, and conservation; patterns
