Complete Question:
Which one is a preposition?
Answer:
of
Step-by-step explanation:
A preposition can be defined as a word that shows or illustrates the relationship between a pronoun or noun and other words in a sentence. Some examples of a preposition used in various literary works in English language are up, below, after, by, against, for, over, at, to, etc.
The main purpose of a preposition as a part of speech is to introduce an object (of, upon), indicate a timeframe (from, by, over), show direction (to, across, along), location or place (at, up, after, below) and to illustrate the spatial or sequential relationship between two or more things, people, place, etc.
Hence, the preposition in the sentence "I am one of those who cannot describe what they do not see." is the word of. It simply means that the speaker belongs to the category of people without the ability to describe what they cannot or do not see.