You’ve written an application that uploads objects onto an S3 bucket. The size of the object varies between 200 – 500 MB. You’ve seen that the application sometimes takes a longer than expected time to upload the object. You want to improve the performance of the application. Which of the following would you consider?

Answer options:

A.Create multiple threads and upload the objects in the multiple threads.
B.Write the items in batches for better performance.
C.Use the Multipart upload API.
D.Enable versioning on the Bucket.

Answer – C
The AWS Documentation mentions the following to support this.
The Multipart Upload API enables you to upload large objects in parts. You can use this API to upload new large objects or copy an existing object (see Operations on Objects).
Multipart uploading is a three-step process: You initiate the upload, you upload the object parts, and after you have uploaded all the parts, you complete the multipart upload. Upon receiving the complete multipart upload request, Amazon S3 constructs the object from the uploaded parts. You can then access the object just as you would any other object in your bucket.
Option A and B are incorrect because both need more changes in the application and are not easier than option
C.Option D is incorrect because enabling versioning does not help to improve the performance of uploading objects. 
For more information on Amazon S3 Multipart file upload, please refer to the below link-
https://docs.aws.amazon.com/AmazonS3/latest/dev/mpuoverview.html