Final answer:
The semantic differential approach developed by Malhotra effectively captures various self-concepts and perceptions of objects such as automobiles and celebrities.
Step-by-step explanation:
The measurement approach developed by Malhotra that is effective in describing the ideal, social, and actual self-concepts of individuals, as well as in describing the images of automobiles and celebrities, is the semantic differential approach (c). This approach involves rating concepts on a scale between two bipolar adjectives, which allows for nuanced assessment of attitudes and perceptions across different self-concepts and objects like automobiles and celebrities. It is useful in a variety of fields, including marketing and social psychology.