The correct option is
B Infundibulum
The corolla can have different shapes when the petals show fusion or the gamopetalous condition. The funnel-shaped corolla is called infundibulum.
A. Bell-shaped corolla is called campanulate, e.g., Campanula.
B. Urn-shaped corolla is called urecolate, e.g., Bryophyllum.
C. Wheel-shaped corolla is called rotate, e.g., Calotropis.
D. Funnel-shaped corolla is called infundibulum, e.g., Petunia.
Hence, the correct answer is 'Infundibulum'.