The choice that combines the given sentences most effectively is: Option C : furnished: their.
<h3>What is sentence correction?</h3>
Sentence correction or sentence improvement is a type of grammatical practice where a sentence is given with a word or a phrase that requires grammatical changes or improvement.
Now, here in the given sentence:
"The plainer rooms are more sparsely <u>furnished. Their</u> architectural features, furnishings, and decorations are just as true to the periods they represent",
The most suitable choice, by sentence correction, to combine the two sentences will be: Furnished: their (option C).
To learn more about sentence correction, refer to the link: brainly.com/question/14632568
#SPJ4
