To attract bees, because they're not colorblind :)
To attract animal/insects to them.
Petals are the most colorful parts of the flower
In most plants, this would be the flower; specifically, the petals.
petals
Petals are the most colorful parts of the flower
The scent that is most attractive to humans is that which comes from flowers.
I believe you are referring to the flower petals, but they are not there to protect the ovary or anything and they often drop off quickly or wither. Flower petals and their bright colors (some of these colors cannot be seen by mammals) are there to attract pollinators (e.g. insects and birds) and guide them towards the center of the flower so that they may efficiently pollinate the ovary.
Most flowers are beautiful. They appear this way in order to attract bugs. When a bug lands on a flower's petals, the flower's pollen will get stuck on the bug's body. When the bug lands on a different flower, the pollen is transferred to the new flower.
Most hibiscus flowers have 5 petals, but there are some varieties that may have 3, 6, or even more petals. It is rare to find hibiscus flowers with exactly 4 petals, but exceptions may exist due to genetic mutations or hybridization.
A geranium has 5 petals on a single flower. If you mean a Pelargonium then 5 on a single and many more on a double or semi-double.f
In most flowers, the petals contain the majority of fragrance, as evidenced by the use of rose and jasmine petals in the distillation of perfume oils.
One of the most important reasons for flowers is to attract bees and insects for pollination.So the flowers are bright Nd attractive by nature.