Lichens, which are capable of initiating ecological succession even on a bare rock, are actually a symbiotic association of

Lichens are a mutualistic symbiotic association between algae (or cyanobacteria) and fungi, where the fungus provides structural support and moisture while the algae produces food through photosynthesis. Option (d) is a common distractor because mosses are also pioneer species that often grow alongside lichens, but they are independent bryophytes rather than internal symbiotic partners. This question tests the core concept of biological mutualism and the role of pioneer organisms in primary ecological succession.