A) Estoy triste de que no haya metro aqua.
Am sad that there are no metro here.
B) Prefiero que tomes un taxi.
I prefer to take a taxi.
C) Es posible que el ferry no hacen la ruta maAtana.
Is it possible that the ferry, may not have a route?
D. Es dudoso que vengan en tren.
I doubt that the train will come,
The Answer is D.- doubt is expressed in this sentence.
I hope this will help.