Using the Modern Rules of Validity, Determine the Quality and Quantity

Using the modern rules of validity, determine the quality and quantity of the unstated premise of the following enthymeme. All chairs are furniture.
$\underline{\quad\quad\quad\quad\quad\quad\quad}$
Some furniture is not comfortable.

A) particular negative
B) particular affirmative
C) universal negative
D) universal affirmative
E) There is not enough information to determine the answer.