The correct option is B Corymb
The inflorescence is the arrangement of the flower. If the main axis is shortened and lower flower possess longer stalk so that all flowers are brought to the same level. Such type of inflorescence is called as corymb. But if the main axis is short and flower possess stalk of equal length so that flowers are seen to spread out from a common point and such type of inflorescence is called as umbel. Catkin is the modified spike inflorescence that possesses unisexual flowers and Spadix is also a modified inflorescence with the fleshy axis. Thus, the correct answer is option B.