Question

An example of special racemose inflorescence is
a. Umbel
b. Cyathium
c. Verticillaster
d. Capitulum

Answer 1

Racemose inflorescence classified as compound raceme or panicle if the main axis of the inflorescence is branched and lateral branches carry flowers in a simple raceme fashion.

Complete answer:
An umbel is an inflorescence composed of a number of small flower stalks that extend from a common point, much like umbrella ribs (called pedicels).

A cyathium is one of the specialised pseudanthium (false flowers) of the genus Euphorbia (Euphorbiaceae) that form the inflorescence of plants.

Verticillaster is an inflorescence in which, as in many minutes, the flowers are arranged in an apparent whorl, actually consisting of a pair of opposite axillary, normally sessile, cymes.

The only racemose inflorescence with a flattened receptacle is the Asteraceae capitulum. The distinctive inflorescence, a capitulum, or jaw. The inflorescence may be composed of ray flowers, disc flowers or both ray and disc flowers, depending on the tribe. Each flower's ovary is located below the corolla and stamens attachment, a position referred to as epigynous or inferior.
The head of the flower is a special category of inflorescence in which anything from a small cluster to hundreds or even thousands of flowers are clustered together to create a single arrangement identical to a single flower.
Pseudanthia, the actual flowers of a pseudanthium, take numerous shapes,
They're usually called florets. A flower head or capitulum is a very contracted raceme in which the share of single sessile flowers on an expanded stem is borne.

Hence, the correct answer is option (D).

Note: In acropetal succession, the arrangement in which the youngest flower is present close to the apex and older near the base, i.e., is called racemose inflorescence. In this case, however, the growth point does not interrupt the growth and shapes the lateral flowers continuously.