Final answer:
The maturity stage in the PLC lasts longer and poses strong challenges to marketing managers.
Step-by-step explanation:
In the Product Life Cycle (PLC), the stage that normally lasts longer and poses strong challenges to marketing managers is the maturity stage.
The maturity stage is characterized by a stable rate of sales growth and high market saturation. During this stage, the market becomes more competitive as more companies enter the market, leading to increased competition and price pressure.
Marketing managers face challenges such as maintaining market share, dealing with product differentiation, and finding new target markets. They need to focus on strategies like product innovation, market segmentation, and marketing communications to stay competitive in the mature stage.