Which code segment should you insert at line 04?

You use Microsoft Visual Studio 2010 and Microsoft .NET Framework 4.0 to create an application.
The application connects to a Microsoft SQL Server database.
The application uses the following object query to load a product from the database.
(Line numbers are included for reference only.)

01 using (AdventureWorksEntities advWorksContext = new AdventureWorksEntities())
02 {
03 ObjectQuery <Product> productQuery = advWorksContext.Product.Where(“it.ProductID = 900”);
04 …
05 }

You need to log the command that the query executes against the data source. Which code segment should you insert at line 04?

A.
Trace.WriteLine(productQuery.ToString());

B.
Trace.WriteLine(productQuery.ToTraceString());

C.
Trace.WriteLine(productQuery.CommandText);

D.
Trace.WriteLine(((IQueryable)productQuery).Expression);

Explanation:
CHAPTER 8 Developing Reliable Applications
Lesson 1: Monitoring and Collecting Performance Data
Accessing SQL Generated by the Entity Framework (page 509)