Select the most appropriate medium composition typically reported for industrial streptomycin fermentation (by Streptomyces):

Introduction / Context:
Streptomycin, an aminoglycoside antibiotic, is produced by Streptomyces species using complex media rich in carbon, nitrogen, vitamins, and minerals. Buffering with calcium carbonate is classic in many Streptomyces fermentations to stabilize pH during production.

Given Data / Assumptions:

• Goal: identify a representative medium composition.
• Key components: carbohydrate (glucose), complex nitrogen (soybean meal, peptone), growth factors (malt extract), buffer (CaCO3).
• Exact recipes vary, but certain combinations are textbook-standard.

Concept / Approach:
Media for streptomycin often combines glucose (carbon), soybean meal/peptone (nitrogen sources), malt extract (vitamins/growth factors), and CaCO3 for pH control and buffering. In contrast, simple salts like ammonium chloride are not typical buffers for these processes and sodium chloride is not standard in the core high-yield recipes.

Step-by-Step Solution:

Verification / Alternative check:
Classic fermentation protocols for Streptomyces list CaCO3 as a mild buffer to maintain optimal pH and enhance production.

Why Other Options Are Wrong:

• NaCl or ammonium salts: not the representative buffering system here.
• Minimal sets lacking CaCO3 miss a hallmark of many Streptomyces media.

Common Pitfalls:
Assuming any complex nitrogen source automatically implies a complete production medium; buffer selection matters for yield.

Final Answer:
Soybean meal, glucose, peptone, malt extract, calcium carbonate