Here's why:
* Prepositions are words that show the relationship between a noun or pronoun and another word in the sentence. They typically indicate location, time, or direction. Examples include: "on," "in," "at," "to," "from," "with," "by," etc.
* Compound prepositions are formed by combining two or more words, usually a preposition and an adverb. Examples include: "according to," "in front of," "because of," "instead of," etc.
"In spite of" acts as a single preposition expressing the idea of "despite" or "regardless of." It connects the noun or pronoun following it to the rest of the sentence, showing that something happened despite a certain circumstance.
Example:
* In spite of the rain, the game continued. ("In spite of" connects the noun "rain" to the rest of the sentence, showing that the game continued despite the rain.)