Question

a scientist is studying bacteria. he notices that when a culture of bacteria placed near a heat source, the population flourished and then eventually dies as the temperature continues to rise. he decides to investigate this phenomenon. which hypothesis might the scientist develop? populations of bacteria can be quite large. some bacteria can tolerate heat better than others. the bacteria grow best within a narrow temperature range. bacteria need a constant supply of food in order to thrive.

Explanation:

The scientist observes bacteria flourishing then dying as temperature rises. We analyze each option:

• "Populations of bacteria can be quite large" is about population size, not temperature effect. Eliminate.
• "Some bacteria can tolerate heat better than others" compares different bacteria, but the observation is about one culture's response to temperature change. Eliminate.
• "The bacteria grow best within a narrow temperature range" fits: they flourish (grow well) in an initial temp range, then die as temp exceeds that range, implying a narrow optimal range.
• "Bacteria need a constant supply of food to thrive" is about food, not temperature. Eliminate.

Answer:

C. The bacteria grow best within a narrow temperature range.