A five-storeyed building with floors from I to V is painted using four different colours and only one colour is used to paint a floor. Consider the following statements: The middle three floors are painted in different colours. The second (II) and the fourth (IV) floors are painted in different colours. The first (I) and the fifth (V) floors are painted red. To ensure that any two consecutive floors have different colours

Answer is (b). Precondition: Five floors are painted with four different colors. Statement 1: The statement that the middle three floors are painted in different colors does not ensure that any two consecutive floors will have different colors, as floors I and II or floors IV and V could potentially have the same color. Statement 2: Similarly, stating that the second (II) and the fourth (IV) floors are painted in different colors does not guarantee that any two consecutive floors will have different colors, as floors I and II, II and III, III and IV, or IV and V could share the same color. Statement 3: This statement ensures that any two consecutive floors will have different colors since there are only four colors to be used, leaving the remaining three floors with different colors. Therefore, the correct answer is (b)