A company is hosting an Amazon API Gateway REST API that calls a single AWS Lambda function. The function is infrequently invoked by multiple clients at the same time. The code performance is optimal, but the company wants to optimize the startup time of the function.
What can a developer do to optimize the initialization of the function?

A. Enable API Gateway caching for the REST API.
B. Configure provisioned concurrency for the Lambda function.
C. Use Lambda proxy integration for the REST API.
D. Configure AWS Global Accelerator for the Lambda function.