Helianthus annuus, the common sunflower, is a large annual forb of the genus "Helianthus" grown as a crop for its edible oil and edible fruits (sunflower seeds).
 This sunflower species is also used as bird food, as livestock forage (as a meal or a silage plant), and in some industrial applications.
 The plant was first domesticated in the Americas.
 Wild "Helianthus annuus" is a widely branched annual plant with many flower heads.
 The domestic sunflower, however, often possesses only a single large inflorescence (flower head) atop an unbranched stem.
 The name "sunflower" may derive from the flower's head's shape, which resembles the sun, or from the impression that the blooming plant appears to slowly turn its flower towards the sun as the latter moves across the sky on a daily basis.
The small marsh flower Cotula coronopifolia bears the common names brass buttons, golden buttons, and buttonweed.
 The flower heads are bright yellow discoid heads that look like thick buttons.
 Individual plants spread stems along the ground and send up the knobby flowers at intervals.
 The plant is native to southern Africa, but it has been introduced to other parts of the world (Europe, North + South America, etc.).
Styphelia is a genus of shrubs in the heather family, Ericaceae.
 The genus is endemic to Australia and the Pacific Islands.
Safflower ("Carthamus tinctorius") is a highly branched, herbaceous, thistle-like annual plant.
 It is commercially cultivated for vegetable oil extracted from the seeds. Plants are 30 to tall with globular flower heads having yellow, orange, or red flowers. Each branch will usually have from one to five flower heads containing 15 to 20 seeds per head.
 Safflower is native to arid environments having seasonal rain.
 It grows a deep taproot which enables it to thrive in such environments.
Xerochrysum bracteatum, commonly known as the golden everlasting or strawflower, is a flowering plant in the family Asteraceae native to Australia.
 Described by Étienne Pierre Ventenat in 1803, it was known as "Helichrysum bracteatum" for many years before being transferred to a new genus "Xerochrysum" in 1990.
 It grows as a woody or herbaceous perennial or annual shrub up to a metre (3 ft) tall with green or grey leafy foliage.
 Golden yellow or white flower heads are produced from spring to autumn; their distinctive feature is the papery bracts that resemble petals.
 The species is widespread, growing in a variety of habitats across the country, from rainforest margins to deserts and subalpine areas.
 The golden everlasting serves as food for various larvae of lepidopterans (butterflies and moths), and adult butterflies, hoverflies, native bees, small beetles, and grasshoppers visit the flower heads.
Grindelia stricta is a species of flowering plant in the daisy family known by the common names Oregon gumplant, Oregon gumweed and (in Britain and Ireland) coastal gumplant.
 It is native to the west coast of North America from California to Alaska, where it is a resident of coastal plant communities such as those in marshes and beaches.
 This plant is variable in appearance, taking the form of a weedlike perennial herb forming low clumps to a sprawling subshrub growing erect to heights exceeding one meter.
 Its foliage and stems are green to rusty red or purplish and the plant may be hairy to hairless.
 The fleshy leaves are green, often with red edges and veining, and are up to 15 centimeters in length on large plants.
 The inflorescence holds one or more flower heads each up to 5 centimeters wide.
 The flower head is a cup of thick erect or recurved green phyllaries.
 Yellow disc florets fill the center of the flower head and there is a fringe of yellow ray florets around the circumference.
 The head produces copious white exudate, especially in the early stages of blooming.
Pyrethrum was a genus of several Old World plants now classified as "Chrysanthemum" or "Tanacetum" (e.g., "C. coccineum") which are cultivated as ornamentals for their showy flower heads.
 Pyrethrum continues to be used as a common name for plants formerly included in the genus "Pyrethrum".
 Pyrethrum is also the name of a natural insecticide made from the dried flower heads of Chrysanthemum cinerariifolium and Chrysanthemum coccineum.
Celosia is a small genus of edible and ornamental plants in the amaranth family, Amaranthaceae.
 The generic name is derived from the Ancient Greek word κήλεος ("kḗleos" ), meaning "burning," and refers to the flame-like flower heads.
 Species are commonly known as woolflowers, or, if the flower heads are crested by fasciation, cockscombs.
 The plants are well known in East Africa’s highlands and are used under their Swahili name, mfungu.
Carthamus lanatus is a species of thistle known as woolly distaff thistle, downy safflower or saffron thistle.
 It is closely related to safflower, which is in the same genus.
 This annual plant is a native of the Mediterranean Basin, but it is familiar in other places where it was introduced and has become a noxious weed, such as in parts of North America and southern Australia with similar climates.
 This is a spiny, glandular, woolly plant, which often looks like it is covered in spiderweb due to its fine tangled fibers.
 It has a pale stem which may reach a meter in height, and rigid, pointed, very spiny leaves.
 The flower head has many long, sharp phyllaries that can be up to several centimeters long, and often bend backwards (recurved).
 The disc florets are bright yellow.
 One plant can produce many stems which mat together due to their spininess and form a small thicket.
 The fruit is an achene about half a centimeter long with many rigid pappus scales.
Nabalus albus, the white rattlesnake-root, also known as Boott's rattlesnake-root or white lettuce, is a plant in the family Asteraceae, native to Canada and the Eastern United States.
 Details of the flower heads are needed to separate this species from others in the rattlesnake-root genus (Nabalus).
 The Iroquois applied a poultice of the roots of white rattlesnake root to rattlesnake bites.
 It can be found growing in forests, woodlands, and anthropogenic habitats.
 The flower head has ray flowers only, meaning all of the individual flowers of the flower head have a strap-shaped ray, which may or may not have teeth at the very tip of the ray.
 The colors vary from blue to purple, pink to red, or white.
 The leaf blade length can be between 40 to 300 mm.
 while the flower head width can be 3 to 5 mm.

Question: Which plant has more flower heads and comes in more colors, Safflower or Styphelia?
Answer: Safflower