You are designing an ASP.NET Web application.
You have the following requirements:
Users must be allowed to save their work in progress on one computer and to continue the work on another computer.
Data that is submitted for processing must be valid, and invalid data must be rejected.
Primary key constraints within the database must be enabled at all times.
The application must store only data that is entered by the user.
You need to design data validation to support the requirements.
Which two approaches should you recommend? (Each correct answer presents part of the solution. Choose two.)
A.
Store temporary form data as XML in a database table.
B.
Use validators to verify the data when the user submits a form.
C.
Add an isTemporary column to each database table, and set all columns to allow null values.
D.
Provide default values for the database columns, and submit the form with user-entered values when the user saves the form.