Please answer the following question: Lek (river) - The Lek (Dutch pronunciation: [lk]) is a river in the western Netherlands of some 60 km in length. It is the continuation of the Nederrijn after the Kromme Rijn branches off at the town of Wijk bij Duurstede. The main westbound waterway is hereafter called the Lek River. Given a choice of categories company, educational institution, artist, athlete, office holder, mean of transportation, building, natural place, village, animal, plant, album, film or written work, the text refers to which one?
A:
Natural Place