The correct option is B Cypsela
Cypsela Is a simple one seeded fruit which has pappus. This is a dry fruit which is very tiny belonging to the family Asteraceae and also has an additional silken, furry, hairy structure called as the pappus. This plays an important role in seed dispersal.
Achene is also a dry fruit but does not belong to asteraceae, and lacks pappus.
A nut is much bigger in size unlike the cypsella and lacks pappus, though it is a dry fruit.
As regma fruit belongs to euphorbiaceae and cypsella belongs to Asteraceae.
Thus, the correct answer is option B.