Many Texans wanted Texas to immediately join the United States after winning independence from Mexico. However, the U. S. delayed the decision to annex Texas for nearly ten years. Which of the following reasons best explains the delay?

I: Controversy over slavery
II: Manifest Destiny
III: Concern over conflict with Mexico
IV: Discovery of Gold in California

A) I and III
B) II and III
C) I and IV
D) I and II