The Prebisch-Singer hypothesis states that primary commodity-dependent developing nations face a long-run structural decline in their terms of trade. Which of the following relationships between the income elasticity of demand for primary commodities (YEDpYED_pYEDp) and manufactured goods (YEDmYED_mYEDm) provides the theoretical foundation for this hypothesis?
0<YEDp<10 < YED_p < 10<YEDp<1 and YEDm>1YED_m > 1YEDm>1
YEDp>1YED_p > 1YEDp>1 and 0<YEDm<10 < YED_m < 10<YEDm<1
YEDp<0YED_p < 0YEDp<0 and YEDm>1YED_m > 1YEDm>1
YEDp>1YED_p > 1YEDp>1 and YEDm>1YED_m > 1YEDm>1
