A company wants to use Amazon DynamoDB for maintaining metadata on its forums. See the sample data set in the image below.

A DevOps Engineer is required to define the table schema with the partition key, the sort key, the local secondary index, projected attributes, and fetch operations. The schema should support the following example searches using the least provisioned read capacity units to minimize cost.

• Search within ForumName for items where the subject starts with ‘a’.
• Search forums within the given LastPostDateTime time frame.
• Return the thread value where LastPostDateTime is within the last three months.

Which schema meets the requirements?

A. Use Subject as the primary key and ForumName as the sort key. Have LSI with LastPostDateTime as the sort key and fetch operations for thread.
B. Use ForumName as the primary key and Subject as the sort key. Have LSI with LastPostDateTime as the sort key and the projected attribute thread.
C. Use ForumName as the primary key and Subject as the sort key. Have LSI with Thread as the sort key and the projected attribute LastPostDateTime.
D. Use Subject as the primary key and ForumName as the sort key. Have LSI with Thread as the sort key and fetch operations for LastPostDateTime.