What do Pirkle et al., 2015 identify as major problems from trade liberalization policies for many low-income nations in West Africa? A. Trade liberalization policies reduce investment in domestic food production and encourage food-importation. B. Import-dependent nations are at greater risk of food insecurity when world food prices fluctuate. C. Trade liberalization continues to support cash-crop monoculture (defined as growing a single type of crop that can be exported for cash such as cotton), rather than growing foods that provides nutritional value for the local population. D. All of the above