Choose two statements that are right.

It is not a good idea to combine different data sources for deep analysis. It’s much better to concentrate on just one data source, e.g. logfile
Combining data from logfiles and webcrawls helps compare simulated and real crawler behavior
If you overlay your sitemap with your logfiles, you may see a lack of internal links that shows that the site architecture is not working properly

The correct answer is:

Combining data from logfiles and webcrawls helps compare simulated and real crawler behavior.
If you overlay your sitemap with your logfiles, you may see a lack of internal links that shows that the site architecture is not working properly.