Was the Spanish Use of Horses Helpful in Conquering the Incas

Was the Spanish use of horses helpful in conquering the Incas?

A) Yes, they were intimidated by them
B) Yes, in that horses were considered sacred to the Incas
C) No, it turns out that horses could not travel the mountainous terrain like lamas
D) No, every horse that Pizarro brought over died of sickness before any battles actually happened