The answer to the question stated above is:
Muslims find guidance on everyday issues such as family, marriage and business in both the Qur'an and the Sunna. It's letter C.
Choices to this question are:
A)In the Qur'an
b)In the Sunna
c)In both the Qur'an and the Sunna
d)In neither the Qur'an nor the Sunna