First answer, D: sad, helplessly, shocked.
In the excerpt one can notice right away that, even though Gregor would like his situation to be nothing but a dream, the author makes sure to let the reader know that it is not a dream. The rain hitting the pain makes him realize he is sad, or it accentuates his sadness. Lying on his back, like a bug, he feels helpless, and hearing his voice shocks him.
Second answer, C: Gregor was shocked when he heard his own voice answering, it could hardly be recognized as the voice he had had before.
From the beginning of the excerpt one can feel Gregor´s despair at having been turned into a bug, and though his new bodily condition is quite shocking, it isn´t until he tries to put everything into words —by trying to answer his mother´s question— that he notices that he can´t provide a reasonable explanation —not even phrase it: his body and his voice were no longer those he had had before.
