Question

In Bougainvillea, weak stems rise up support by clinging to it with the help of curved thorns, such plants are called as
(a)tendrils
(b)hooks
(c)offsets
(d)scramblers

Answer 1

Bougainvillea is a plant that grows weak shoots that grow on other plants for a long time. A rambling rose is another example of a plant that falls into this category. There are long, flexible stems in these plants that may look like vines, but they cannot climb on their own.

Complete answer:
One of the plants that fall into the group of scramblers is Bougainvillea. There are long, flexible, curved stem thorns in these plants that help them grasp neighboring stems and ascend.
Scramblers have flexible, long stems that resemble vines, but are climbing and rambling roses and Bougainvillea without a way of grasping support, for example. These thorns are used by such plants to help in climbing.
Scramblers often have thorns that help them grasp adjacent stems, you will need to tack them into place if you want these plants to "climb" up a trellis, arbor, or pergola and possibly attach them with wire or sturdy string.

Additional Information:
Tendrils:
A good example of a plant that uses tendrils for climbing is peas. Tendrils are skinny, wiry structures that actually reach around in the air around the stem of the plant until they come into contact with something that they can catch. The tendril curls once contact is made, forming a coil which allows the plant to adjust the degree of tension or pull on the support.
Hooks:
Bur plants use hooks for dispersal. Burs are primarily seeds that have hooks inside them, or fruits. Xanthium, Arctium, Geum, etc are a few examples of such plants. Burs are attached using their hooks to the fur of animals and the seeds of the plants are distributed in this way.
Offsets:
An offset is a small, virtually complete daughter plant that has been naturally and asexually developed on the mother plant in botany and horticulture. Offsets occur when meristem regions of plants differentiate into a new plant with the potential to become self-sustaining, such as axillary buds or homologous structures. In species developing underground storage organs, such as bulbs, corms, and tubers, this is especially common.
So, the correct answer is, ‘scramblers’.

Note: Bougainvillea is a genus of ornamental vines, bushes, or trees that are thorny. From Brazil, west to Peru, and south to southern Argentina, it is native to Eastern South America. Between four and 18 species in the genus are recognized by various authors. The inflorescence is made up of large sepal-like, colorful bracts surrounding three simple waxy flowers. In most warm climates, such as Florida and South Carolina, and across the Mediterranean Basin, Bougainvillea is a common ornamental plant.