Microtubles are the constituents of spindle fibres, centrioles and cilia. These are a component of the cytoskeleton, found throughout the cytoplasm. They are very important in a number of cellular processes. They are involved in maintaining the structure of the cell and, together with microfilaments and intermediate filaments. They also make up the internal structure of cilia and flagella. They provide platforms for intracellular transport and are involved in a variety of cellular processes, including the movement of secretory vesicles, organelles, and intracellular macromolecular assemblies. They are also involved in chromosome separation and are the major constituents of mitotic spindles, which are used to pull apart eukaryotic chromosomes. Most centrioles are made up of nine sets of microtubule triplets, arranged in a cylinder.
So, the correct answer is option B.