ANS:B - saturated

The maximum heat transfer coefficient from steam heating will be attained when the steam is saturated. When steam is saturated, it is in a state where it exists in equilibrium with liquid water at a given temperature and pressure. Saturated steam contains the maximum amount of latent heat and is capable of transferring heat most effectively. As a result, saturated steam provides the highest heat transfer coefficients compared to other steam states. When steam is supersaturated or wet, it contains liquid water droplets in addition to vapor. This can lead to reduced heat transfer coefficients due to the lower thermal conductivity of liquid water compared to steam. Wet steam can also cause erosion and damage to heat transfer surfaces. Therefore, saturated steam is preferred for achieving the maximum heat transfer coefficient in steam heating applications.