To answer this question, we need to understand the enhancements made to the Visual Studio Debugger. Let's go through each option to determine which statement is not true:
Option A) Search in the Breakpoints window, label breakpoints, import and export breakpoints - This option is true. The Visual Studio Debugger has enhancements that allow you to search for breakpoints, label breakpoints, and import/export breakpoints.
Option B) There is no support for debugging mixed-mode native and managed code on 64-bit operating systems - This statement is not true. The Visual Studio Debugger does support debugging mixed-mode native and managed code on 64-bit operating systems.
Option C) You can use the Parallel Stacks and Parallel Tasks debugger tool windows to visualize and debug parallel code that is written in C++, C#, or VB - This option is true. The Visual Studio Debugger includes the Parallel Stacks and Parallel Tasks debugger tool windows that allow you to visualize and debug parallel code written in C++, C#, or VB.
Option D) A newly redesigned Threads window provides filtering, call-stack searching and expansion, and grouping - This option is true. The Visual Studio Debugger includes a newly redesigned Threads window that provides filtering, call-stack searching and expansion, and grouping.
Option E) WPF debugging enhancements include enhanced tracing to view events in your WPF application and WPF Tree Visualizer to inspect and search the WPF tree - This option is true. The Visual Studio Debugger includes WPF debugging enhancements that allow you to view events in your WPF application and use the WPF Tree Visualizer to inspect and search the WPF tree.
Based on the analysis above, the statement that is not true is Option B) There is no support for debugging mixed-mode native and managed code on 64-bit operating systems. The correct answer is B.