During the maturity stage of the product life cycle

a. sales volumes rise rapidly as new customers make initial purchases and earlier purchasers rebuy.

b. financial losses are common as firms incur heavy promotion and R and D costs.

c. innovations or shifts in consumer preferences bring about a decline in industry sales.

d. the public becomes acquainted with the product's merits and begins to accept it.

e. some firms try to differentiate their products on the basis of quality, reliability, and service.