Suppose that P is the statement "n + 1 = n + 2". What is wrong with the following proof that the statement P is true for all non negative integers n?You assume that P(k) is true for some positive integer k, that is, that k+1 = k+2. Then you add 1 to both sides of this equation to obtain k+2 = k+3; therefore P(k+1) is true. By the principle of mathematical induction P is true for all non-negative integers n.

• The proof is incorrect because you cannot add one to both sides of the equation in the inductive step
• There is nothing wrong with this proof
• The proof is incorrect because there is no basis step Correct
• The proof is incorrect because the statement used in the inductive hypothesis is incorrect