The correct options are
A Invasion of Ottoman Turks
B Invention of the printing press
D New geographical inventions and crusades
Around 1453 CE Ottoman Turks invaded Constantinople, and with its fall, scholars from Constantinople took abode in Italy. Their wealth of knowledge became the reason for the Renaissance. Gutenberg from Germany invented the printing press, and this facilitated the availability of multiple copies of various books. Contact with the East through new trade routes, geographical discoveries, and crusades also furthered the cause of the Renaissance.