UGC NET CSE | October 2020 | Part 1 | Question: 23

Question

If some pens are pencils but no pencil is sharpener then

1. All pencils are pens
2. Some sharpeners are pencils
3. Some pens are not sharpener
4. Some pencils are not pens

Choose the correct answer from the options given below:

• A. $(i)$ and $(iii)$ only
• B. $(ii)$ and $(iii)$ only
• C. $(i)$ and $(iv)$ only
• D. $(ii)$ and $(iv)$ only

Answer 1

None of the answer is correct 

1. All pencils are pens ( it is not neccessarity true but possible )
2. Some sharpeners are pencils (pencil and sharpner are disjoint set so it is wrong
3. Some pens are not sharpener (true as some pens are pencil and no pencil is sharpner)
4. Some pencils are not pens (it is not neccessarily true only a possibility)

 

only statement c is always true