Here's a problem to solve: Nutrient runoff can cause algal blooms in waterways. Which genetically modified organisms could help reduce algal blooms?

Among the 4 following options, which is the correct answer?

- A: pigs that are modified to have more fat
 
- B: cows that are modified to require less feed
 
- C: corn that is modified to be resistant to herbicides
 
- D: soybeans that are modified to make their own insecticide
 