My youngest brother had a surprise waiting for me when I went next door after work this afternoon . He came out with what looked like a book at first and I asked him if it was for me . Well , it was for me and it 's ' The Last Unicorn ' movie on DVD ! Was I excited and my jaw dropped open .
According to the above context, choose the best option to answer the following question.
Question: What may be the reason for their jaw dropping open ?
Options:
A. Because they were bored .
B. Because they were thirsty .
C. Because they were so surprised .
D. Because they were hungry .


C