The correct answer is C. Spyder is a cross-platform Qt-based open-source Python IDE, not R IDE.
A. qgrid is an interactive grid for sorting and filtering DataFrames. This is correct. qgrid is a Python package that provides an interactive grid for sorting and filtering DataFrames. It is based on the Qt toolkit and can be used with any Python data analysis library, such as Pandas.
B. Pandas DataFrames implement repr_html methods which are utilized by IPython Notebook. This is correct. Pandas DataFrames implement the repr_html method, which is used by IPython Notebook to render DataFrames in a formatted HTML table.
C. Spyder is a cross-platform Qt-based open-source R IDE. This is incorrect. Spyder is a cross-platform Qt-based open-source Python IDE. It is a popular IDE for Python development, and it includes features such as a code editor, a debugger, and a variable explorer.
D. None of the mentioned. This is incorrect. Option C is the only incorrect statement.