Which two actions should you perform?

You create a class that inherits the SPPersistedObject class. The class has a field named Field1.

You need to ensure that Field1 can be serialized and stored in the SharePoint configuration database.

Which two actions should you perform? (Each correct answer presents part of the solution. Choose two)

A.
Add the default empty constructor.

B.
Mark Field1 with the [Persisted] attribute.

C.
Mark Field1 with the [Serializable] attribute.

D.
Set the value of the SPWeb.AllowUnsafeUpdate property.

Explanation:
MNEMONIC RULE: “[Persisted] + empty constructor”

SPPersistedObject Class
http://msdn.microsoft.com/en-us/library/microsoft.sharepoint.administration.sppersistedobject.aspx

The skinny on SPPersistedObject and the Hierarchical Object Store in SharePoint 2010
http://www.chaholl.com/archive/2011/01/30/the-skinny-on-sppersistedobject-and-the-hierarchical-object-store-in.aspx