Answer:
B. the appearance of lichens and mosses in an area where a glacier has recently melted away
Explanation:
Ecological succession, which refers to the series of changes that occurs over time in an ecosystem, can be of two types namely: primary succession and secondary succession.
Primary succession is a succession that involves an area where no form of life has grown previously, hence, the area of land is barren e.g bare rock. Primary succession is first colonized by species called PIONEER SPECIES e.g. lichens, mosses etc.
According to this question, "the appearance of lichens and mosses (pioneer species) in an area where a glacier has recently melted away" is an example of PRIMARY SUCCESSION.
A frog gets rid of it's urine through the kidneys because the heart pumps blood throughout the body, the lungs are used to take in O2 molecules and gills are use to filter out the hydrogen in HO2 so they can breathe under water. However the kidneys are part of the waste disposal system (what makes us need trip to the bathroom ever now and then) therefore that is the answer.<span />
The answer you are looking for is True
Used by people is the answer. :-)
