Refer to Figure 2-1. Which arrow represents the flow of goods and services? Figure 2-1 Two sets of opposing squares, linked by two loops. The left and right squares indicate the actors, firms and households, respectively. The second set of opposing squares at the top and bottom, indicate the two markets: the market for goods and services and the market for factors of production, again respectively. For the loops, there is an inner loop flowing clockwise and an outer loop flowing counterclockwise. The top portion of the outer loop is labeled, A, and the bottom portion of that loop is, D. For the inner loop, the top portion is labeled, B, and the lower portion is labeled, C