Let you create a chatbot to use as an Interactive Voice Response (IVR).

• A. Amazon Comprehend
• B. Amazon Lex
• C. Amazon Forecast
• D. AWS IoT Greengrass

Answer: (B)

Building an IVR-style chatbot requires handling spoken language and guiding the conversation with prompts and actions. Amazon Lex provides that by offering automatic speech recognition and natural language understanding, along with built-in dialogue management. You can define intents with slots, manage multi-turn conversations, and fulfill actions as the user progresses through the IVR flow. Lex can drive how the bot greets callers, asks for information, validates input, and routes to the right outcome, all in a voice-enabled or text-based interface. For phone-based IVR, Lex integrates smoothly with Amazon Connect, letting calls be processed by the bot to deliver a natural, interactive experience.

Other services don’t fit this use case: Amazon Comprehend analyzes text for sentiment and entities but isn’t built for conversational flows; Amazon Forecast is for time-series forecasting; AWS IoT Greengrass is for edge computing with IoT devices.