This is called “Jockers of microbiological park”

The correct option is mycoplasma.

Here is the step-by-step explanation of why Mycoplasma is known as the "Joker of the microbiological park" (often also referred to as the "Jokers of the plant kingdom"):

1. Lack of a Cell Wall:
Unlike most other bacteria, fungi, and plant cells, species of the genus Mycoplasma completely lack a cell wall surrounding their cell membrane. The cell wall is the structure that typically gives microbes a rigid, defined shape.

2. Pleomorphism (Ability to Change Shape):
Because they lack a rigid cell wall, Mycoplasma organisms are highly pleomorphic. This means they can naturally alter their shape and size in response to environmental conditions, taking on various forms such as spherical, filamentous, star-shaped, or irregular structures. This shape-shifting ability is analogous to a "joker" or a buffoon changing their appearance.

3. Smallest Living Cells:
They are also notable for being among the smallest free-living microorganisms discovered, capable of surviving without oxygen (facultative anaerobes) and passing through filters that retain typical bacteria.

Therefore, due to their unique cell-wall-less structure and their resulting ability to change into diverse shapes, they are famously designated as the "Jokers of the microbiological park".