Consider the life cycles in Bryophytes and Pteridophytes. Which of the following statements accurately highlights a key evolutionary transition or a distinguishing feature between them?
Correct: C
Option C is correct. Both Bryophytes and Pteridophytes are termed 'amphibians of the plant kingdom' due to their reliance on water for the transfer of flagellated antherozoids during fertilization. A major evolutionary advancement observed in Pteridophytes is the differentiation of the sporophyte into true roots, stems, and leaves, which are absent in Bryophytes whose plant body is thallus-like or has simple, undifferentiated structures. Option A is incorrect because in Bryophytes, the gametophyte is dominant, and the sporophyte is dependent, whereas in Pteridophytes, the sporophyte is dominant and independent. Option B is incorrect because in Bryophytes, the gametophyte is free-living. Option D is incorrect because most Bryophytes are homosporous, and while some Pteridophytes are heterosporous (e.g., Selaginella, Salvinia), many are homosporous (e.g., most ferns, Equisetum), making 'invariably heterosporous' false.