Which one of the following waterways has more economic and strategic significance?

Which of the following canals is used as an inland waterway in Southern Germany?

Through which one of the following straits does a tunnel connect the United Kingdom and France?

Which one of the following lakes of West Africa has become dry and turned into a desert?

Which of the following is the second deepest and the longest freshwater lake in the world?

Which one of the following can one come across if one travels through the Strait of Malacca?