The dew point temperature lines on psychrometric charts are straight inclined sloping downwards to the right. When relative humidity of moist air is 100%, then_________________?

The dew point temperature lines on psychrometric charts are straight inclined slog downwards to the right. When relative humidity of moist air is 100%, then_________________?

A. Wet bulb temperature=dry bulb temperature
B. Wet bulb temperature=dew point temperature
C. Saturation temperature=dew point temperature
D. All ‘A’, ‘B’ & ‘C’