Complete the sentence with the correct option:
I have never come _______anyone as rude as him
A. Across
B. To
C. Around
D. At

Hint: Preposition, are group of words or any class of non-inflecting words typically employed to connect a following noun or a pronoun, in an adjectival or adverbial sense, with some other word: a particle used with a noun or pronoun to make phrase limiting to some other word.

Complete answer
Let’s discuss the given options and find the correct answer.
>Across: “Across” is a type of preposition which indicates to, toward or from the far side of (something that lies between two points of interest). For example , we rowed across the river. It also means something on the opposite side of something. For example, the store is across the street.
>To: “to” is a type of preposition which indicates destination, used to indicate the target or recipient of an action, used to indicate result of action, used to indicate a resulting feeling or emotion, used after an adjective to indicate its application.
>Around: Around” is a type of preposition which means round and round. For example, she wore a gold chain around her neck.
>At: “at” is a preposition which is used to indicate time, direction, which denotes a price, indicates a position on a scale or in a series. For example, at 5’o clock, he threw the stone at me, the offer was at $ 30,000.

Hence, the option A: Across, is the correct answer.

Note: In this sentence the complete word should make a phrasal verb. Phrasal verb is a phrase which is formed with a verb and a particle that is a preposition or an adverb. The phrasal verb always makes a meaning which is different from the literal meaning of the individual words.