<span>These are formed by adding an apostrophe and an "s" to the noun.
</span><span>
The plural possessive form of each noun:
</span>
1. Friend -----> friends'
<span>2. Box -------> boxes' </span>
<span>3. House -----> houses' </span>
But is a coordinating conjunction. That's not the correct answer. (The) is not a coordinating conjunction. You use the acronym FANBOY for coordinating conjunctions.
F-for
A-and
N-Nor
B-but
O-or
Y-yet
so (the) is not a coordinating conjunction
I hope this helps :)
I don't know what the example is, but taciturnity means quietness. So the answer is D.