What is the primary security advantage of using an API Gateway to mask the 'Topology' of your internal microservices?

1. A It prevents external attackers from discovering the private IP addresses and physical ports of your internal servers, making direct attacks much harder.
2. B It ensures that the internet service provider (ISP) cannot charge you for internal network traffic.
3. C It allows the Gateway to automatically compress internal traffic to 50% of its original size.
4. D It makes it easier for the microservices to run on slower, less expensive hardware.