Temperature preferences: Under ordinary food and clinical conditions, bacteria and fungi generally multiply most rapidly within which temperature range?

Introduction / Context:
Most pathogens and food spoilage organisms are mesophiles, thriving at moderate temperatures that overlap with ambient and body temperatures. Recognizing this range informs food safety controls and incubation choices in the laboratory.

Given Data / Assumptions:

• We consider “general” microbial growth of common bacteria and many yeasts/molds.
• Specialists like psychrophiles or thermophiles are excluded from the general statement.

Concept / Approach:
Mesophiles grow best approximately between 20–45 °C, with many pathogens optimized near 35–37 °C. For a broad practical range, 16–38 °C captures conditions where multiplication is typically efficient in foods and clinical specimens before selective temperature controls are applied.

Step-by-Step Solution:
Identify the category: mesophiles dominate foodborne and clinical contexts. Compare ranges: sub-16 °C slows growth (refrigeration), >38 °C selects thermotolerant species. Choose the range that best aligns with rapid, general multiplication.

Verification / Alternative check:
Food codes and lab protocols commonly specify incubation at 30–37 °C for many tests, consistent with mesophilic preferences.

Why Other Options Are Wrong:

• Below 16 °C or near-freezing: slows metabolism; mainly psychrotrophs grow.
• Above 38 °C: favors thermotolerant/thermophilic species; not “general.”
• None of these: incorrect; mesophilic range is well established.

Common Pitfalls:
Assuming all fungi are psychrophiles; many molds also grow well at moderate temperatures.

Final Answer:
Between 16–38 °C (mesophilic range).