P, Q, R and S are four logical statements such that if P is true, then Q is true; if Q is true, then R is true; and if S is false, then both Q and R is true.. Then it follows that
Explanation
Checking the given options:
1) if S is false, then both Q and R is true → This statement follows because as given in the question 'if S is false, then both Q and R is true'.
2) If at least one of Q and R is true, then S is false → This statement is not followed because it is complementary to the statement given in question 'if S is false, then both Q and R is true'.
3) If P is true, then S is false → we can not conclude this statement because in question there is no relation given between P and S.
4) If Q is true, then S is true → This statement is not followed because it is given in question 'if S is false, then both Q and R is true'.
Hence, 'if S is false, then both Q and R is true' is the correct answer
