Perianth when not divided into calyx and corolla
Whorl of sepals
Whorl of bracts
Whorl of bracteoles
Whorl of tepals
When the perianth is not divided into distinct calyx and corolla, it is referred to as a whorl of tepals. Tepals are undifferentiated floral organs that resemble and function as both sepals and petals. They cannot be clearly distinguished into distinct sepals and petals, and they typically have a similar appearance and texture.
This condition is commonly observed in flowers that lack a clear distinction between sepals and petals, and the perianth is composed of tepals. Examples of flowers with tepals include tulips or lilies.
Hence, the correct answer is option 4.