You are developing a banking application that will interact with a DynamoDB table. The table is going to take in a lot of read and write operations. Which of the following would be the ideal partition key for the DynamoDB table to ensure ideal performance?

Answer options:

A.CustomerID
B.CustomerName
C.Location
D.Age

Answer - A
The AWS Documentation gives the ideal way to construct partition Keys.
Recommendations for partition keys
Use high-cardinality attributes. These attributes have distinct values for each item, like e-mailid, employee_no, customerid, sessionid, orderid, and so on.
Use composite attributes. Try to combine more than one attribute to form a unique key, if that meets your access pattern. For example, consider an orders table with customerid+productid+countrycode as the partition key and order_date as the sort key.
Option B is incorrect because CustomerName may be the same.
Option C is incorrect because some customers can have the same location.
Option D is incorrect because Age can be the same for customers.
For more information on choosing the right partition Key, please refer to the below Link-
https://aws.amazon.com/blogs/database/choosing-the-right-dynamodb-partition-key/