A scientist was examining a large boulder that was covered with lichens (a combination of fungi and algae). He chipped a piece of the rock and placed it under a microscope. He observed that the surface of the rock was breaking down underneath the lichen. Which was the scientist most likely observing?

Pick the answer from these options

Possible answers: --the interaction between abiotic factors --the effects of chemical weathering --the process of deposition --the effects of abrasion
the effects of chemical weathering