To calculate the work done when raising an object, we can use the formula:
\[ \text{Work} = \text{Force} \times \text{Distance} \times \cos(\theta) \]
In this case, the force (weight of the box) is 50 newtons and the distance raised is 0.5 meters. Since the person is lifting the box vertically, the angle \(\theta\) between the force and the direction of motion is 0 degrees, for which \(\cos(0) = 1\).
So, the work done is:
\[ \text{Work} = 50 , \text{N} \times 0.5 , \text{m} \times 1 = 25 , \text{joules} \]
Thus, the correct answer is 25 joules.