Which of the following is an explanation?

a. Since these stray dogs have been neutered, they are someone’s pets.
b. Since the dance studio was established, it has never produced a professional dancer.
c. Since the company is doing well, I will give my employees raises.
d. Since the future cannot be known, no one truly has the gift of fortune-telling.
e. Since the spaceship crashed in Roswell, that is where the aliens will want to build their embassy.