Final answer:
A fall in supply of microcomputers is most likely to explain the increase in the number of computers being sold at lower prices in the computer market.
Step-by-step explanation:
A fall in supply is most likely to explain the increase in the number of computers being sold at lower prices in the computer market. A fall in supply means that there is a decrease in the quantity of microcomputers available in the market. This could be due to factors such as a shortage of semiconductor materials or increased cost of computer components. When the supply of microcomputers decreases, it can lead to higher prices in the market.
In a demand and supply diagram, a fall in supply would be represented by a leftward shift of the supply curve. This indicates that at any given price, the quantity supplied is lower than before. As a result, the equilibrium price in the market may increase, leading to lower prices for consumers.