Given the Following Sorites: All N Are P

Multiple Choice

Given the following sorites: All N are P.
Some N are F.
All F are R.
All R are A.
Some A are not P.
This sorites is:

A) Invalid because one of the middle terms is undistributed.
B) Invalid because it has affirmative premises and a negative conclusion.
C) Invalid because it has three universal premises and a particular conclusion.
D) Valid because a particular premise requires a particular conclusion.
E) Valid because no rules are broken.