Answer:
The correct option is "a"
Explanation:
There are several books on this historical topic of Spanish history. One of the many books written on this topic is "Spain's Emigrants to the New World 1492-1592" written by the author V. Aubrey Neasham.
Form the study of history we come the know that the first option - option a Many of the early arrivals came to direct Native American labor, is correct.