Lady Montagu introduced the inoculation <u>of smallpox</u> to Europe.
Explanation:
A prepositional phrase is a group of words that consists of a preposition, its object, and the words that modify the object. Prepositions are words used to connect other words within a sentence and express the relationship between them (e.g. space and time).
In the given sentence, a prepositional phrase can be introduced by changing the words<em> smallpox inoculation</em> into <em>inoculation of smallpox</em>. The preposition here is <em>of </em>and its object is <em>smallpox</em>.
