Concept:The average propensity to consume (APC) shows the fraction of income that people spend on consumption.Explanation:The formula for APC is:APC=YCHere, aggregate consumption C is 400 and aggregate income Y is 500.Substitute the values:APC=500400=0.80This means that out of every 1 of income, households spend 0.80.Answer:Option B. 0.80