Step 1: Definition.
Misrepresentation is a false statement of fact, made innocently, that induces another party to enter into a contract.
Step 2: Analysis of statements.
(a) Correct — the false statement must be material to the contract.
(b) Incorrect — an unwarranted statement (without reasonable grounds) can indeed cause misrepresentation if it induces the contract.
(c) Correct — belief in truth does not prevent liability for misrepresentation.
(d) Correct — inducing a mistake as to the substance of the subject matter is misrepresentation.
Step 3: Conclusion.
Since (b) is contrary to the legal definition, it is the incorrect statement. \[ \boxed{(b)} \]
Match List-I with List-II\[\begin{array}{|c|c|} \hline \textbf{List-1} & \textbf{List-II} \\ \hline \text{(A) Hadley v. Baxendale} & \text{(1) Undue Influence} \\ \hline \text{(B) Henkel v. Pape} & \text{(II) Coercion} \\ \hline \text{(C) Manu Singh v. Umadat Pandey} & \text{(III) Quantum of Damages} \\ \hline \text{(D) Chikkam Amiraju v. Seshamma} & \text{(IV) Mistake} \\ \hline \end{array}\]