The navigable rivers in Western Europe have historically impacted economic development in the region by —

A. providing for the irrigation of arid land
B. blocking the spread of epidemic diseases
C. preventing the advancement of land armies
D. facilitating the movement of goods and people

Based on what you know about the location of the earth in relation to the sun, why is this called the goldilocks zone in other galaxies? a. it's a region that exhibits a weak gravitational pull, thus maintaining a safe distance from the sun. b. it's an area that doesn't experience any major weather events that could cause mass extinctions. c. it's an area that's an optimal distance from the sun for potentially supporting life. d. it's a region that's unaffected by asteroid or meteor impacts.