Correct option: (b) eukaryotic flagella
The 9+2 fibrillar arrangement is present in eukaryotic flagella. This arrangement refers to the 9 fused pairs of microtubules on the outside of a cylinder and the 2 unfused microtubules in the centre.
The core of the flagella, called axoneme, has nine pairs of doublets of radially arranged peripheral microtubules and a pair of centrally located microtubules. Such an arrangement of axonemal microtubules is referred to as 9 + 2 array.
