the air temperature is 70 degrees, and the relative humidity is 90 which conclusions can be made.

the temperature must rise in order for air to become saturated with water vapor
the amount of water vapor in the air is 90% of what he air con hold
the air holds little water vapor and is relatively dry
the dew point temperature is 90% of the air temperature

Based on the given information, the conclusion that can be made is:

- The amount of water vapor in the air is 90% of what the air can hold.