This is a moderately difficult question on interpretation of ratios. Bear in mind that this is a ‘Yes No’ type of DS question. So, getting a ‘No’ is also an accepted answer.
From statement I alone, we have the ratio of sheep in stalls C and E but not the others. Therefore, this statement is insufficient to answer the main question with a definite YES or a definite NO.
From statement II alone, we have the ratio of sheep in stalls E and F, but not the others. Again, this is sufficient to give a unique answer to the main question.
When we combine statements I and II, we can find out the ratio of C:E:F to be 10:15:6. This ratio refers to the number of sheep in the respective stalls. Therefore, the smallest possible values for the actual number of sheep in these stalls are 10, 15 and 6.
This means, these 3 stalls have a total of 31 sheep. We are left with 4 stalls but only 2 sheep. Even if we accommodate one sheep each in 2 stalls, 2 stalls will be left empty.
“Is there at least one sheep in every stall?” – From the above, the answer is a clear NO.
So, this data is sufficient and the correct answer option is C.
When you arrive at the ratio 10:15:6, there are two things that will keep running in parallel in your mind:
A ratio does not represent the actual value always. So numbers in the ratio of 10:15:6 can be (10,15,6) or (20,30,12) and so on.
Because of the above, can I assume the actual values as 10, 15 and 6?
Clearly, the answer is YES, because of the constraint that the total number of sheep are 33 only.
Hope this helps!