The correct option is
B May
Modal Verbs show us the attitude of the speaker to what is being said or done. The term "modal" means expressing mood and mood is a way to express the attitude of the speaker.The usage of modal Verbs differ according to the the type of sentences.
Option B is correct because the modal verb "may" shows the mood of positive hope of maximum possibility and can be expressed in exclamatory sentences.
Whereas, option A suggests certainty and is generally used in interrogative sentences.; option C contains the word "shall" which is used only with first person (i.e. I, We) to form the future forms and not with second person; and option D contains the modal verb "can" which is generally used in interrogative sentences when it is place at the beginning.