The correct option is
D In the above data, the marks obtained by the students are given. So it is a numerical data.
In the above data, grades obtained by the students are given, so it is not a numerical data.
In the above data, the number of employees working in a different organization are given, so it is a numerical data.
In the above data, the number of pairs available for different items are given, so it is a numerical data.
So except (b), all are numerical data.
Hence, options (a), (c) and (d) are correct.