In a vapour compression refrigeration cycle, the refrigerant enters the compressor in saturated vapour state at evaporator pressure, with specific enthalpy equal to $250$ $\text{kJ/kg}$. The exit of the compressor is superheated at condenser pressure with specific enthalpy equal to $300$ $\text{kJ/kg}$. At the condenser exit, the refrigerant is throttled to the evaporator pressure. The coefficient of performance $\text{(COP)}$ of the cycle is $3$. If the specific enthalpy of the saturated liquid at evaporator pressure is $50$ $\text{kJ/kg}$, then the dryness fraction of the refrigerant at entry to evaporator is _______________.

1. $0.2$
2. $0.25$
3. $0.3$
4. $0.35$