Final answer:
The substance that caused the largest temperature change in water has a low specific heat capacity, meaning it transfers more energy per gram to the water, as compared to substances with higher specific heats like water.
Step-by-step explanation:
If a substance caused the largest temperature change in water, it suggests that the substance has a low specific heat capacity. Specific heat capacity is defined as the amount of heat energy required to raise the temperature of 1 gram of the substance by 1°C. Water, known for its high specific heat capacity, absorbs more heat without a large temperature increase. So, if we compare substances and how much they change the water's temperature, the one that causes the largest temperature change must transfer more energy per gram to the water and thus has a lower specific heat capacity than water.
Therefore, the correct answer is:
b. Substance 2, low specific heat, as it caused the largest temperature change in the water, indicating a low specific heat capacity compared to water with its high specific heat capacity.