Final answer:
Over the past 50 years, the number of small family farms has decreased due to industrialization in agriculture. Meanwhile, meat consumption patterns have shifted, with beef consumption decreasing and chicken consumption increasing in the United States. The correct answer is b. the number of small family farms.
Step-by-step explanation:
The question pertains to changes over the past 50 years concerning consumption, agricultural practices, and food production. Among the options provided, the number of small family farms has indeed decreased. This decline is related to the industrial transition in agriculture, which involved fundamental changes in agricultural practices, leading to a more energy-intensive farming process where fossil fuels became a significant input. Concurrently, the consumption of meat has seen shifts as well; for instance, in the United States, while the per-person consumption of chicken has increased, beef consumption has decreased.
On the other side of the spectrum, the use of food crops for biofuel production has increased due to policies promoting biofuels as an alternative to fossil fuels, especially over the past couple of decades. Furthermore, the average per-capita consumption of calories has generally risen globally as a part of nutritional transitions associated with changes in income levels and consumption patterns. Therefore, the correct answer reflecting a decrease over the past 50 years is the number of small family farms.