Using the Modern Rules of Validity, Find the Unstated Premise $\underline{\quad\quad\quad\quad\quad\quad\quad}$

Multiple Choice

Using the modern rules of validity, find the unstated premise of the following enthymeme. All chairs are furniture.
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Some furniture is not comfortable.

A) No chair is comfortable.
B) No comfortable thing is a chair.
C) Some chairs are not comfortable.
D) Some comfortable things are not chairs.
E) Some chairs are comfortable.