क्रियात्मक अनुसंधान (Action Research) को सबसे सही रूप में किस प्रकार वर्णित किया जा सकता है?

In educational testing and evaluation, the 'validity' of a test refers to:

The primary objective of effective teaching at the higher education level is to:

Match List I (Research Method) with List II (Characteristic): Testbook (a) Survey Method - (III) Collection of data from a large population (b) Experimental Method - (IV) Establishing cause-effect relationships (c) Historical Method - (I) Study of past events using documents and records (d) Case Study Method - (II) In-depth study of a single unit Which match code is correct?