Answer: Option (d) is the correct answer.
Step-by-step explanation:
When a block of steel at 90 degrees Celsius is placed in a bucket of water at 30 degrees Celsius then due to the difference in temperature there will be transfer of heat from hotter substance (steel) to cooler substance (water).
Thus, when heat is released by steel block then its temperature will decrease whereas this heat is gained by water so, its temperature will increase.
Therefore, we can conclude that the temperature of the steel decreases and the temperature of the water increases.