The correct answer is: A. Shorter
The growing season is the period of time each year when plants can grow. It is determined by the amount of sunlight a plant receives. In the northern hemisphere, south-facing hillsides receive more sunlight than north-facing hillsides. This is because the sun is higher in the sky in the southern hemisphere than in the northern hemisphere. As a result, south-facing hillsides have a longer growing season than north-facing hillsides.
Option B is incorrect because north-facing hillsides receive less sunlight than south-facing hillsides. This means that they have a shorter growing season.
Option C is incorrect because there is no evidence to suggest that north-facing hillsides have a more consistent growing season than south-facing hillsides.
Option D is incorrect because there is no evidence to suggest that north-facing hillsides have a more productive growing season than south-facing hillsides.