Which skill of Microsoft office is most critical for research students?

It depends upon method of research u following. Qualitative research doesn't require MS exce. But all type of reserch methods utilize MS word.

In doing research, Microsoft word and excel are really of need. Word Office is necessary for data coding and literature review. Excel is very much important in treating gathered data especially with differential statistics

Excel is most critical for research students because in research data is of great importance and to manipulate data one should know excel.

Data Analysis application of MS Excel