Which one of the following is a saprophytic bryophyte ?

Bryophytes usually grow in moist and shady places. Some bryophytes grow in diverse habitats such as aquatic (eg, Riccia fluitans), epiphytic (eg, Dendroceros and many mosses) saprophytic (eg, Buxbaumia aphylla) and in dry habitats such as dry heaths (eg, Polytrichum juniperinum) deserts (eg, Tortula desertorum) and dry rocks (eg, Porella platyphylla).