Answer: A. Christianity was the only religion allowed in Spain.
Explanation:
After the death of the prophet Muhammed, Muslim armies swept across the known world and reached as far as southern Europe where they took over parts of Spain.
The Reconquista was a period that lasted for 700+ years that saw the Christian Spanish claw back land from the Muslim Moors and it ended with Christianity being the only religion allowed in Spain as the Moor were killed, deported or forced to convert.