Read these excerpts from two passages. Overfishing

"The world faces a calamitous food crisis if we do not stop overfishing. According to the United Nations, about one billion people, mostly in developing countries, rely on fish as their primary source of animal protein. What will they do when the fish run out? That crisis could occur soon. While there will probably never be a time when we do not have fish, there could come a time when we no longer have enough fish. The cause of this fish shortage is overfishing. Overfishing occurs 'when more fish are caught than the population can replace through natural reproduction,' according to the World Wildlife Foundation. Once this occurs, the species is no longer 'sustainable.'"

Aquaculture

"Nutritionists say that seafood is healthier to eat than other kinds of animal protein...Current United States Department of Agriculture (USDA) guidelines suggest that Americans eat two to three seafood meals a week. Unfortunately, most Americans do not consume that amount of fish. However, even if Americans were willing to eat more fish, would the world’s seas be able to provide it? In order to meet even current global consumption rates, experts at the United Nations Food and Agriculture Organization estimate that the world will need another 40 million tons of seafood per year by 2030. Where will all this fish come from? Many people think that the answer is aquaculture."

What is a common theme in these excerpts?

A)The problem of meeting the world's supply of fish, which are experiencing declining populations.

B)Controversy over how many servings of fish should be recommended in USDA food guidelines.

C)The issue of how to feed the world's increasing human population.

D)How to change demand for fish in developing countries that use it as their main source of animal protein.