Budding is observed in

The correct answer is Yeast.

Step-by-step Explanation:

1. What is Budding?
Budding is a form of asexual reproduction in which a new organism develops from a small projection or outgrowth, known as a bud, on the parent body. This bud grows over time and eventually detaches to lead an independent existence, leaving the parent cell intact.

2. Process of Budding in Yeast:
Yeast is a unicellular fungus that commonly reproduces by budding under favorable environmental conditions. The process occurs as follows:
- A tiny bulb-like projection (bud) begins to form on the cell wall of the parent yeast cell.
- The nucleus of the parent yeast cell divides mitotically into two daughter nuclei.
- One of these nuclei migrates into the developing bud.
- The bud grows in size, constricts at the base, and eventually separates from the parent cell to mature into a new, independent yeast cell. Sometimes, multiple buds remain attached to each other, forming a chain of buds.

3. Why Other Options are Incorrect:
- Planaria: Flatworms like Planaria reproduce asexually through fragmentation and possess high regenerative capabilities rather than budding.
- Amoeba: Amoeba is a unicellular organism that typically reproduces by binary fission, where the parent cell splits symmetrically into two equal daughter cells.
- Protonema of mosses: While secondary protonema can reproduce by budding, the primary mode of asexual multiplication in the protonema of mosses is fragmentation.