Who has proposed two-step concept to describe the process of attitude change?

The correct option is Mohsin.

To understand why this is the correct answer, let us look at the concept of attitude change in social psychology:

The "two-step concept" of attitude change was proposed by the Indian psychologist S.M. Mohsin. According to this theory, attitude change takes place in two sequential steps:
1. First Step (Identification): The target person (the one whose attitude is to be changed) identifies with the source of influence (the influencer). The target person develops a positive liking or relationship with the influencer.
2. Second Step (Attitude Alignment): The influencer changes their own attitude or behavior towards the attitude object. Seeing this, the target person also changes their attitude to align with the influencer, maintaining cognitive consistency or harmony in their relationship.

Thus, the two-step concept is specifically attributed to Mohsin, making "Mohsin" the correct answer.