Hi @sharpen7, thanks for your post. In this formal logic drill, you are given one premise and one conclusion, and asked to identify the missing premise. The given premise includes a Y and a C. The conclusion includes a C and a D. We need to find a premise that links the Y and the D.
The given premise is: Y-most-C
Recall that "most" statements can be reversed as "some" statements, as follows: C-some-Y
Let's consider answer choice (A). P: not D ==> not Y the contrapositive is Y ==> D
You can connect this contrapositive with the given premise as reversed, as follows: C-some-Y==>D
Therefore: C-some-D (the given conclusion).
Hope this helps! Please let us know if you have any additional questions.
