Answer: Amazon Lex

## Explanation Amazon Lex is the correct AWS service for building conversational chatbots for customer service. Here's why: - **Amazon Lex**: This is AWS's service for building conversational interfaces using voice and text. It provides the deep learning functionalities of automatic speech recognition (ASR) for converting speech to text, and natural language understanding (NLU) to recognize the intent of the text. It's specifically designed for chatbot development. - **AWS Amplify**: This is a development platform for building mobile and web applications, not specifically for chatbots. - **Amazon Comprehend**: This is a natural language processing (NLP) service that uses machine learning to find insights and relationships in text, but it's not specifically designed for building conversational interfaces. - **Amazon Polly**: This is a text-to-speech service that converts text into lifelike speech, which could be used as part of a chatbot solution but doesn't provide the core chatbot functionality itself. Amazon Lex is the comprehensive solution that provides the full conversational AI capabilities needed for customer service chatbots, including intent recognition, slot filling, and dialog management.

Author: Ritesh Yadav