Which of the following is not a stem modification?

Units of............ are united or free.

Sometimes sepals are modified into hairy structures which are useful in dispersal of seeds. These are called

What is the scientific name of $Bougainvillea$ $spectabilis$?

Starch grains in latex are

Given below are two statements $:$
Statement $- I :$ The arrangement of ovules within the ovary is known as aestivation.
Statement $- II :$ The mode of arrangement of sepals and petals in floral bud with respect to the other members of the same whorl is known as placentation.
In the light of the above statements,choose the correct answer from the options given below $:$