a) Intelligent tiering would not meet business requirement specifications, as tiering depends on file usage.
b) Use of versioning is required to handle archiving of original submissions. Use of lower cost One Zone IA is justified for blog summaries as these can be recreated if needed.
c) Lambda functions are not the most efficient way to achieve these requirements as they must be created and the code maintained.
d) As per b, but lacking versioning, so unable to automate archiving of original submission, and does not make use of S3 One Zone IA