The workers were all wearing black cap, shoes, trousers and orange T-shirts. The uniform was all similar. Identify the principle of management followed here.

The correct option is Discipline.

Step-by-step Explanation:

1. Understanding the Principle of Discipline:
In classical management theory, particularly Henri Fayol's principles of management, Discipline refers to the obedience, respect for authority, and adherence to established rules, regulations, and codes of conduct within an organization. It is essential for the smooth and systematic functioning of any business enterprise.

2. Analyzing the Given Scenario:
The scenario states that all workers were wearing a specific uniform (black cap, shoes, trousers, and orange T-shirts). Wearing the prescribed uniform is a clear organizational rule and part of the workplace code of conduct. By wearing this uniform consistently, the workers are demonstrating their adherence to the company's rules and regulations, which is a direct application of the principle of Discipline.

3. Why Other Options are Incorrect:
- Order: This principle states that there should be a designated place for everything (material order) and everyone (social order) to avoid confusion and maximize efficiency. It does not deal with wearing uniforms.
- Unity of Command: This principle dictates that an individual employee should receive orders and instructions from only one direct superior to avoid conflict and confusion.
- Unity of Direction: This principle states that activities sharing the same objective should be directed by a single manager using one plan, ensuring coordination and focused effort.