When a famous film actress pledges her eyes for donation after death, it is observed that there is a surge in the number of people doing the same. What factor influences this change in people's attitude?

Attractiveness

The correct answer is Option (2) → Attractiveness

Here, people are influenced because a famous film actress (an attractive and admired source) made the pledge. The factor at work is the attractiveness of the source, which increases persuasion and attitude change.