Which of the following is an example of a tautology?
Either it is raining or it is not raining.
If it is raining, then it is not sunny.
If it is raining, then it is not snowing.
If it is not raining, then it is sunny.
A tautology is a compound proposition that is always true, regardless of the truth values of its components.
Option (1) is correct as in this case, the proposition is always true because it is either raining or it is not raining, there are no other possibilities.
Option (2) is incorrect as it is a conditional statement, not a tautology.
Option (3) is incorrect as it is also a conditional statement, but it is not a tautology because there are situations in which it could be false, such as when it is both raining and snowing.
Option (4) is incorrect as it is a conditional statement that is also not a tautology because there are situations in which it could be false, such as when it is not raining and not sunny.
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