An application uses the GetItem operation to read data from a DynamoDB table. What strategy can be used to reduce the size of the read operations and increase read efficiency?

Answer options:

A.Use Filter Expression.
B.Use Pagination.
C.Use Parallel Scan.
D.Use Projection Expression.

Answer: D
Option A is incorrect because filter expression can be used with Scan operations to filter the results returned by the scan operation. It cannot be used to make GetItem operations more efficient.
Option B is incorrect because Pagination is used with Scan operations to divide the result set of the Scan operation into pages. It cannot be used to make GetItem operations more efficient.
Option C is incorrect because Parallel Scans allows multi-threaded applications to perform Scan operations quicker. It cannot be used to make GetItem operations more efficient.
Option D is CORRECT because Projection Expressions can be used to limit the attributes returned by the GetItem operation and thus reduce the size of the read operation.
Reference:
https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/Expressions.ProjectionExpressions.html