Answer:
The answer to this question is B. Christian boys taken from conquered territories and raised as special forces.
Step-by-step explanation:
The Janissaries were Christian boys, that were taken as salves from the Balkan region (Southeast Europe) that ended up in Anatolia (west Asia) and were indoctrinated into Islam and circumcised.
They were made to go through rigorous training, and they earned the rank of Janissary upon reaching 24 or 25 years of age.