From the words or group of words lettered A to D, choose the word or group of words that best completes each of the following sentences: My uncle was not su...

From the words or group of words lettered A to D, choose the word or group of words that best completes each of the following sentences:
My uncle was not sure...........the strange guests were

Answer Details

The word that best completes the sentence is "who" as it refers to people, and the sentence is about strange guests. "Which" refers to things, "whom" is the object form of "who," and "what" refers to things or unknown objects.