ANS:B - it will undergo no change until

• If a solution of eutectic composition is cooled, it will undergo no change until reaching the eutectic temperature. At the eutectic composition, a eutectic mixture forms, which has the lowest melting point among all possible mixtures of the components. As the solution is cooled, its temperature decreases. However, until it reaches the eutectic temperature, there will be no change in the system. Once the eutectic temperature is reached, the eutectic mixture will begin to solidify, forming a eutectic solid. This process occurs without any change in temperature until all of the eutectic mixture has solidified. So, until reaching the eutectic temperature, the system will undergo no change.