Explanation: The underlined word is **amalgamation**. Amalgamation means the action, process, or result of combining or uniting. It is used correctly for: (i) Combining colors. (ii) Combining companies. It is used incorrectly for: (iii) The amalgamation of metals is a complex chemical process. While 'amalgamation' is a specific term for an alloy of mercury with another metal, generally in a non-specific context for a chemical process involving metals, 'combination' or 'alloying' is more appropriate, or more specifically 'alloy formation'. The note provided states that 'amalgamation' in (iii) should be replaced with **'combination'**. Therefore, (iii) is the wrong application.