The knob like structures present on the hyphae are referred as (1) a) Spores

b) Sporangium

c) Fronds

d) Sori

[b] The sporangia are knob-like structures.

They are present at the top of the thread-like structures called hyphae.

They are dispersive, i.e. they are scattered by rain, wind or insects.

answer; benefit; harmed;

answer; nociceptive pain;