I remember that book. well he never gave up and he used his heart so much it exploded
After the colapse of western romain empire was the dark ages also know as the Middle Ages or the Medieval period which was from the fifth to 15th century.
Taj Mahal was designed by Ustad Isha Khan who was ordered to design a building which would be a mix of Indian, Turkish, Persian and Islamic architecture. I assume then that the correct answer is D.