Fern:

• Ferns typically require soil and moisture to grow, as they rely on water-conducting tissues and need a substrate to anchor their roots.

Lichen:

• Lichens are a symbiotic association between a fungus and an algae or cyanobacteria.
• Lichens are well-adapted to survive on surfaces without soil, such as rocks, tree bark, and even bare ground, as they can obtain their nutrients and moisture directly from the air and precipitation.
• Lichens are sensitive to airborne pollutants, such as sulfur dioxide (SO2), nitrogen oxides (NOx), ozone (O3), and heavy metals (like lead and mercury). Sulfur dioxide, for instance, causes chlorosis (yellowing) and necrosis (cell death) in lichen thalli. This sensitivity makes lichens an effective indicator of air quality.

Moss:

• Mosses are non-vascular plants that can grow on surfaces without soil, such as rocks, tree trunks, and even roofs.
• Mosses have specialised structures that allow them to absorb water and nutrients directly from the environment.

Mushrooms:

• Mushrooms are the reproductive structures of fungi, and they typically require a substrate, such as decaying organic matter, to grow. Mushrooms are not able to directly survive on a surface without soil or a nutrient-rich medium.

Therefore, among the given options, lichens and mosses are the most likely to be found surviving on a surface without soil in the natural environment.