Final answer:
In a list, the Unique function is used to ignore duplicates and return only a single instance of each item. Sort, Average, and Transpose do not perform this function, they have their own distinct purposes in data manipulation.
Step-by-step explanation:
The function that ignores duplicates in a list and returns a single instance of each item is the Unique function. This function scans the list or range provided, identifies duplicate entries, and excludes them from its output, thereby providing a list of unique items only, with each instance represented just once.
For example, if you have a list with the values (1, 2, 2, 3, 4, 4, 4, 5), using the Unique function on this list would return (1, 2, 3, 4, 5) as the result.
The options provided such as Sort, Average, and Transpose have different functionalities:
- Sort orders the items in a list according to specified criteria but does not remove duplicates.
- Average computes the mean value of a series of numbers but does not exclude duplicates.
- Transpose changes a vertical range of cells to a horizontal range, or vice versa, without affecting duplication.
Therefore, the correct answer to this question is B. Unique.