The Spanish were motivated to colonize in the New World for several reasons. The applicable options from your list are:
B. Expand their territory
D. Spread the Catholic faith
E. Look for gold
While addressing overcrowding (A) may have been a contributing factor for some individuals, it was not a primary motivation for Spanish colonization. Stopping Native American uprisings (C) is also not a main reason; in fact, Spanish colonization often led to conflicts and uprisings.