Step 1: Understand the importance of marketing in business.
Marketing is crucial for businesses to reach customers, understand their needs, and create strategies to satisfy those needs.
Step 2: Evaluate the options.
- Marketing is compulsory for businesses because it helps in customer acquisition, market expansion, and revenue generation.
- While it may be considered a luxury or unnecessary in very specific circumstances, marketing is generally compulsory for business success.
Step 3: Conclude.
The correct answer is that marketing is compulsory for businesses.
Final Answer:
\[
\boxed{\text{Compulsory}}
\]