Spore dissemination in some liverworts is aided by
The capsule of liverworts contains hygroscopic structures called elaters, along with spores. Elaters are hygroscopic in nature. In dry weather they lose water and become twisted. When the atmosphere is moist, they become untwisted and cause a jerking action. Due to this the spore mass loosens and spores are carried out by air currents. Hence the correct answer is A.
Indusium, calyptra and peristome teeth are all characteristics of the capsule of mosses.