Step 1: Understanding the Concept:
Sweetened condensed milk can have specific defects.
Mould buttons is a common defect.
Step 2: Key Formula or Approach:
No specific formula.
Need to know the causes of defects in condensed milk.
Step 3: Detailed Explanation:
Mould buttons defect is caused by Catemularia fuliginea.
This fungus grows on the surface.
Micrococcus pyogenes causes a different defect.
Pseudomonas fluorescens causes a defect in milk.
Thermobacterium mathiacelle is a thermophilic bacterium.
Thus, Catemularia fuliginea causes mould buttons.
Step 4: Final Answer:
Mould buttons defect is due to Catemularia fuliginea.
Hence, the correct option is (C).
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