As in Spain, the Only Income Tax in New Spain

As in Spain, the only income tax in New Spain was the __________.

A) "Real" tax, which was paid directly to the crown on the king's birthday.
B) Export tax, a flat percentage of all materials that had been sent out of the country.
C) Tithe paid to the church, which the administration, at times, used for its own purposes.
D) Slave tax, an effort to diminish reliance on the Portuguese slave trade.