Question

From among the given alternatives, identify the missing premiss.

1st Premiss: If a plane triangle is possible, then perfect straight line is possible

2nd Premiss: If perfect straight line is possible, then Euclid is right

3rd Premiss:  ?

4th Premiss: But Riemann is right.

Conclusion:  Therefore a plane triangle is not possible.

Options

• If Riemann is right, then Euclid is right

• If Riemann is wrong, then Euclid is right

• If Euclid is right, then Riemann is wrong

• If Riemann is right, then Euclid is not wrong

Answer 1

If Euclid is right, then Riemann is wrong

Explanation:

'But' word in the fourth premises requires something in contrast with the statement. Only statement 'If Euclid is right, then Riemann is wrong' brings out such contrast.