Amalgamation is a form of:

The correct answer is Option (2) → complete consolidation

In an amalgamation two or more companies combine and lose their separate identity, their businesses being taken over by a new or an existing company. Since the units merge fully into one, it is a form of complete consolidation. A federation, a cartel and a pool are loose combinations in which each unit keeps its separate existence.

Note: This topic is not covered in any edition of the NCERT Accountancy textbook.