Step 1: Understanding the Concept:
The NIZO method is a butter-making process.
It has specific characteristics.
Step 2: Key Formula or Approach:
No specific formula.
Need to know the NIZO method.
Step 3: Detailed Explanation:
A. No ripening of cream - correct.
B. Sweet buttermilk is obtained - correct.
C. More copper levels in butter - incorrect.
D. More likelihood of rancid flavour - correct.
Thus, A, B, and D are correct.
Step 4: Final Answer:
A, B, and D are correct.
Hence, the correct option is (D).
\bigskip