Final answer:
Gaseous steam has the highest entropy value among the given substances.
Step-by-step explanation:
The substance with the highest entropy value among the given options is c) Gaseous steam. Entropy is a measure of the disorder or randomness in a system. Gaseous steam has the highest entropy because its molecules have the most freedom of motion and are in a highly disordered state. Solid ice has lower entropy because its molecules are in a fixed position and have limited motion.