The fact that the sperm of some gymnosperms have flagella—despite the fact that the sperm do not require water or mobility for fertilization—is evidence of an evolutionary transition between seed and seedless.
a) It would be incorrect to say that some gymnosperms do not have reduced gametophytes
b) because reduced gametophytes are a characteristic of all seed plants.
c) Finally, although in gymnosperms there is only one integument and two sperms are discharged into the pollen tube
d) these facts alone are not evidence of an evolutionary transition from seedless plants.
