Which ones are correct combinations?
i. Cymose inflorescence – Epipetalous – Solanum
ii. Homochlamydeous – Polyandrous – Allium
iii. Axile placentation – Radial leaves – Smilax
iv. Zygomorphic – Diadelphous – Butea
A. i, iv
B. iii, iv
C. i, iii
D. ii, iv

Hint: A flower is viewed symmetrically when every whorl comprises an equivalent number of parts or when the pieces of any one whorl are products of that preceding it. At the point when a flower can be partitioned by a solitary plane into halves, it is zygomorphic, or respectively balanced, as in the snapdragon, orchid, and sweet pea. Solanum contains the nightshades and horse weeds, just as various plants developed for their elaborate flowers and natural products.

Complete answer:
The cymose inflorescence is additionally called a distinct or determinate inflorescence. The development of the peduncle is unmistakable. Here, the terminal bud is adjusted into a blossom. Flowers open in an outward grouping, i.e., flowers open from focus to the fringe of the inflorescence.
Cymose sort of inflorescence is one in which the tip of the fundamental hub closes in a flower. This kind of inflorescence is found in Solanum, where the blossoms are conceived in a solitary plane. The androecium shows the stamens intertwined with the petals, called the epipetalous condition.
Butea has a place with the family Leguminosae. The blossoms are zygomorphic due to the papilionaceous kind of Corolla. These flowers are flowers with the trademark sporadic and butterfly-like corolla found in some plants of the species-rich in Faboideae subfamily of vegetables. The androecium shows the stamens combined in two (9 + 1) groups called the diadelphous condition.

Hence, the correct answer is option (A).

Additional information:
The Allium is portrayed by herbaceous geophyte perennials with genuine bulbs, some of which are borne on rhizomes, and an onion or garlic scent and flavor. The bulbs are lone or bunched and tunicate and the plants are perennialism by the bulbs changing yearly from the base of the old bulbs.
Smilax, class of plants in the family Smilacaceae, comprising around 300 types of the woody or herbaceous plants, differently known as carriers and greenbriers, local to tropical and mild pieces of the world.

Note: Solanum spp. having a place with the family Solanaceae shows the cymose inflorescence wherein the apical aspect of the hub ends with a flower. This is known as the determinate sort of development. The androecium shows the stamens intertwined with the petals, called the epipetalous condition. Butea has a place with the family Leguminosae. The flowers are zygomorphic due to the papilionaceous kind of Corolla. The androecium shows the stamens melded in two (9 + 1) groups called the diadelphous condition.