A fold mountain is a type of mountain formed from the folding of rocks due to compressional forces in the Earth's crust. One of the features of a fold mountain is an anticline, which is an upward arching fold of rock layers, resembling an arch or a dome. This is in contrast to a syncline, which is a downward folding of rock layers. Anticlines and synclines can alternate in fold mountain chains, creating a series of peaks and valleys. Therefore, the correct option is "anticline."