Concept:
Different animal milks vary in fat content.
Step 1: Typical fat values.
• Camel milk $\approx$ 2--3%
• Goat milk $\approx$ 3--4%
• Cow milk $\approx$ 3.5--4%
• Buffalo milk $\approx$ 6--8%
Step 2: Arrange in increasing order.
\[
\text{Camel} < \text{Goat} < \text{Cow} < \text{Buffalo}
\]
Step 3: Mapping to options.
\[
C, B, A, D
\]
Conclusion: Correct answer is option (2).