Which structure form the lower two-thirds of the nose?

I. Lateral nasal cartilage
II. Lesser and greater alar cartilages
III. Septal cartilage
IV. Fibrous fatty tissue
a. I, II, and III only c. I, II, III, and IV
b. I. III, and IV only d. I, II, and IV only

c. I, II, III, and IV