Step 1: Recall types of flower crops.
Chrysanthemums are popular ornamental flowers. They are grown in different forms for decorative and commercial purposes.
Step 2: Types of Chrysanthemum.
- Standard type: Large single flower per stem.
- Spray or bush form: Multiple flowers on one stem.
- Pot-mums: Grown in pots for decoration.
- Coniform: Special shaped form.
Step 3: Eliminate other crops.
Marigold, Gladiolus, and Rose do not have these specific classifications.
Final Answer: \[ \boxed{\text{The types belong to Chrysanthemum.}} \]