Why Did Napoleon Invade Portugal in 1807

Why did Napoleon invade Portugal in 1807?

A) as a response to the threat Portugal posed by not complying with the Continental System
B) with the intention of reinstituting slavery there and expanding French agricultural production
C) as an act of desperation to regain some of the land France had lost there previously
D) in an effort to protect Spain from Portugal and thereby earn Spain's favor
E) as a means of making the Church a governing body there