What can we add to conclude C-some-D? We definitely need a premise with D in it.
What if we connected D and B somehow?
D-some-B
B - >C
C-some-D
D-some-B - >C
C-some-D
D-some-B would work because it would allow us to make a full chain and would let us conclude C-some-D.
We can actually also arrive at the correct answer choice on this question by process of elimination. Every other answer choice has either a not B or not D in it. Additionally, each other answer choice is a some statement, which means it's reversible. 'Some' statements don't have contrapositives, so this means that the not B or not D cannot be negated to get D or B. Thus, we can eliminate every answer choice that has a not B or not D in it since there's no way that we could ever get a B or D from it, and we have a D in the conclusion, not a not D.
Does that make sense? Let us know if you have any other questions!
mystahOctober 19, 2021
Thank for the explanation... I see how eliminating the other options can lead to the right answer; however, with looking at them other answer choices , I have been noticing that "some not " has been coming up more frequently. What is the logical explanation of using some not and is that an inference that could be made? For example:
A-->B B-->C ------ B some C (is this term reversal to B some not C?
