Which of the following statements are true?
A. Truth and falsehood are attributes of individual propositions.
B. Validity can never apply to any single proposition by itself.
C. In a valid argument, all of its premises have to be true.
D. A valid deductive argument cannot have all true premises and a false conclusion.
Choose the most appropriate answer from the options given below:

The correct answer is A, B and D only.

Let us analyze each statement one by one using the foundational concepts of Logic and Argumentation Theory.

Statement A: "Truth and falsehood are attributes of individual propositions."

This statement is TRUE. In logic, a proposition is a declarative statement that is either true or false — and this truth value belongs to the proposition itself, in isolation. For example, "The sky is blue" is a proposition that can independently be evaluated as true or false. Truth and falsity (also called truth values) are properties we assign to individual statements, not to arguments or collections of statements as a whole. This is a core principle of propositional logic.

Statement B: "Validity can never apply to any single proposition by itself."

This statement is TRUE. Validity is a property that applies exclusively to arguments — that is, to a structured relationship between premises and a conclusion. An argument is said to be valid if, whenever all the premises are true, the conclusion must also be true. A single, standalone proposition has no premises and no conclusion — it is simply a claim. Therefore, validity simply does not apply to a single proposition in isolation. You cannot ask "Is this one sentence valid?" — you can only ask "Is this sentence true or false?" Validity requires the structural context of an argument.

Statement C: "In a valid argument, all of its premises have to be true."

This statement is FALSE. This is one of the most common misconceptions in logic. Validity does NOT require that the premises actually be true. A valid argument only requires that the conclusion follows necessarily from the premises — meaning: if the premises were true, the conclusion would have to be true. Consider this classic example:

Premise 1: All cats are fish.
Premise 2: Socrates is a cat.
Conclusion: Therefore, Socrates is a fish.

This argument is valid (the conclusion follows logically from the premises) even though both premises are factually false. Validity is about logical form, not factual accuracy. An argument where all premises are true AND the conclusion is true is called a sound argument — not merely a valid one. Statement C confuses validity with soundness, so it is incorrect.

Statement D: "A valid deductive argument cannot have all true premises and a false conclusion."

This statement is TRUE. This is actually the defining characteristic of a valid deductive argument. By definition, an argument is deductively valid if and only if it is impossible for all the premises to be true while the conclusion is false. In other words, the truth of the premises guarantees the truth of the conclusion. If you ever find that an argument has all true premises but a false conclusion, that is direct proof that the argument is invalid. Statement D correctly captures this definitional truth about deductive validity.

Summary Table:

Since statements A, B, and D are true and statement C is false, the correct answer is A, B and D only.