The dune described as one arrow with a U-shaped form is not clearly defined by the options provided. The closest match might be transverse dunes although they do not fully align with the description given and barchan dunes could be a potential match as well, yet it is not listed in the provided options.
The dune type described, featuring one arrow and one main U-shaped dune with little green, does not align with typical terminology used to classify dunes. However, based on common dune types, this description could perhaps relate to barchan dunes, which are crescent-shaped and commonly found in regions with a unidirectional wind. They are not listed in the given options, but among the provided choices, transverse dunes are often characterized by a series of ridges caused by wind blowing from a consistent direction and could possibly fit the U-shaped criteria if the 'arrow' suggests an alignment perpendicular to the prevailing wind.
Dome dunes are circular with no slip face, which doesn't match the description; seif dunes are long and narrow with sharp crests, not typically U-shaped; and star dunes feature multiple arms radiating from a central point, which does not appear to match the U-shaped description either. Therefore, the description provided does not neatly fit one of the options given.