The introduction of the mechanical clock caused important changes to the society of medieval Europe. A. The increasing complexity of social and economic activity in medieval Europe led to the need for a more dependable means of keeping time than sun and water clocks provided. B. Because they were unreliable even in sunny climates, sun clocks and water clocks were rarely used in Europe, even before the invention of the mechanical clock. C. Before the mechanical clock, every city wanted a large number of timekeepers because more timekeepers allowed for better organization of collective activities. D. Soon after the invention of mechanical clocks, sun and water clocks became obsolete because mechanical clocks were far more accurate. E. Although society in general was quick to adopt the mechanical clock, the Catholic Church resisted it because it challenged the authority of the church F. Clockmakers introduced precision engineering and their clocks gave individuals and groups more control over the organization of their activities.