A and B are coterminal angles if A-B=360.
Thus it has to be 321 or -321. According to the definition, it'll be -321 degrees 50', since 38-(-321) ~ 360
The problem is that when we are talking about degrees ', the ' corresponds to minutes of degrees. 1 degree makes 60' (1 degree is like an hour). So it can't be -321°50', since 50'+50' 1°=60'.
So it's none of the solutions.
Can you continue ?