Marco Polo traveled during the middle ages (AP period 3), for this the communication technology was not very advanced and Western Europe didn't really know the situation of East Asia and vice versa. When Marco Polo explained his travels to the Europeans of the greatness of China many Europeans decided to go and see for themselves if this greatness was indeed true. When the Europeans arrived in China they were very impressed and a new promotion of travel to China emerged, INCREASING China's economy.
One of the major long term effects of the recognition of Christianity in Constantinople was that Christians were no longer persecuted, which led to Christianity becoming a major religion in Europe.
I would say D. sorry if not.
The expert testimony of forensic scientists are convincing because they use state of the art and cutting edge methods to determine different factors which is their job. They are able to tell, based on a fingerprint, to whom this fingerprint belonged, given that these people have the fingerprints in the first place in a database.