Which of the following are pioneer species in primary succession ?

In primary succession pioneer species are

lichens, algae and fungi and other abiotic factors.

These pioneer species start to normalize the habitat. Primary succession bigin on rock formation, such as volcanoes or mountains or in a place with no organisms or soil.

Primary succession begins in barren areas, such as on bare rock exposed by a retreating glacier. The first inhabitants are lichens or plants—those that can survive in such an environment. Over hundreds of years these “pioneer species” convert the rock into soil that can support simple plants such as grasses.

the dark variety, as they are not visible on the dark tree barks

explanation:

answer; the tunica intima also called tunica interna, consists of elastic fibers,connective tissue and smooth muscle cells;