The graph shows information about four species of bacteria and their reproductive rates at different temperatures - HSC - SSCE Biology - Question 3 - 2002 - Paper 1

Upon reviewing the graph, it is evident that each bacteria species exhibits a specific temperature range in which their reproductive rates are optimal. Specifically:

• Species W shows a peak at lower temperatures but declines significantly as temperatures increase.
• Species X displays a broader range of temperatures with a gradual increase and decrease in reproductive rate.
• Species Y peaks at moderate temperatures, showing limited reproductive capacity at high and low extremes.
• Species Z demonstrates a significant drop in reproductive rate at both ends of the temperature spectrum.

Based on these observations, we can draw the conclusion that:

• Individual species reproduce in a relatively narrow range of temperatures. This supports option (D) over the other options, as the other statements do not accurately reflect the graph's data.