Truth be told, it could be two. A would make sense in that the way the sentence is worded, the turtle herself seems weak. while C is also true to the word dragging as that would make it's movements awkward and difficult. I'd say your best bet would be C as turtles heavy backs and it's slowly speed would make the term "Dragging" make more sense.
C. the turtle’s movements are awkward and difficult.
Explanation:
The verb to drag means pulling forcefully with difficulty. As a result, the turtle struggles to move because of her hard protective shell, which has thick bony plates on it, so the it moves slowly in not very deep waters and through the water plants.
The atmosphere created by this setting is the wide desert he was in had so many dunes that he was lost in the middle of it, surrounded by a huge wilderness.
