<span>A) ability to align himself with powerful groups
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Answer:
Christian leaders of the Byzantine Empire feel worried about the Muslim Ottomans which taking over territory so close to the Byzantine Empire.
Explanation:
Christian leaders of the Byzantine Empire feel worried about the Muslim Ottomans who are taking control of the areas which are close to the Byzantine Empire because they know that Muslims did not stop and after these areas, the Muslim Ottomans also attack on the Byzantine Empire in order to conquer it and expand their empire so the leaders of Byzantine Empire start struggling to stop the Muslim Ottomans to enter in their lands.
1)Tetzel sold indulgences
2)A. Emphasis on hard work
C. Elaborate new church building
3)d. Pieter Brueghel
4)d. that god had already determined who was saved and who was not
5)b. by emphasizing the role of good deeds in achieving salvation
I'm pretty sure it's either A or B. I hope this helps!