Why Did the Spanish Struggle to Colonize Arizona and Texas

Why did the Spanish struggle to colonize Arizona and Texas?

A) The Spanish had no interest in those territories.
B) The Indians of those territories thwarted Spanish efforts to establish Catholic missions.
C) Anglo-Americans had dominated the territory since the early eighteenth century.
D) The Pope did not recognize those territories as areas of Spanish influence.
E) France had already colonized those territories.