There are numerous kinds of shampoo, including vitamin$-$enriched, fruit$-$enhanced, color$-$sensitive$,$ therapeutic, and so on$.$ Shampoo that simply promises to clean hair, however, has seen declining sales, has little or no advertising, and has been phased out by most manufacturers. Shampoo that makes no other promise than to clean hair is in the $\_\_\_\_\_\_\_\_$ stage of its product life cycle.

Group of answer choices

maturity

introduction

repositioning

decline