Final answer:
The percentage of GMO crops grown by developing nations varies and can be high, low, or non-existent.
Step-by-step explanation:
The percentage of GMO crops grown by developing nations varies between developing nations (option D). While some developing nations may have a high percentage of GMO crops, others may have a low percentage or no GMO crops at all.
For example, in the soybean-corn ecosystem of the central United States, more than 90% of soybean seeds planted are genetically modified. However, this may not be the case in other developing nations.
It is important to note that the use of GMOs in agriculture is likely to increase in the coming years due to their potential benefits in improving crop yield and resilience.