A local bakery produces a variety of pastries and the ingredients they require. The sales of their pastries have risen. However, the monthly income from these sales has not increased, as competition has compelled the bakery to lower the prices of its pastries. Unfortunately, the bakery has not been able to reduce the cost of producing a pastry. Therefore, despite the rise in pastry sales, the bakery must be contributing less to its overall profits than before.

Which of the following, if true, most seriously undermines this argument?