Computational problems often involve organizing and manipulating data. The problem that specifically deals with arranging items or sequences in a particular order is sorting. Sorting algorithms are fundamental in computer science, used to arrange data elements (like numbers or strings) in ascending, descending, alphabetical, or other specified orders.
Therefore, Sorting is the correct answer. Option A, 'Searching,' involves finding a specific item within a collection, not rearranging the entire set. Option B, 'Indexing,' refers to creating a map or reference to data locations for faster retrieval, without altering the data's physical arrangement. Option D, 'None,' is incorrect because sorting perfectly describes the task of arrangement and sequencing.