How to show a list of names to select when the the cursor is pointed to a particular cell

Dear Experts,

Pls see the attached excel table.

In this table there are some details that are repeatedly typed by the data entry operator in the columns B, C and E. To save time, I need to show those details(some details are already typed for information)to appear automatically in the particular cell when the mouse pointer is placed inside that cell. Then, she can simply select and by entering the required detail from the list that appears.

Pls kindly help me get this done, and also explain how it should be done if I want to apply the same mechanism in another case.

Thanks in advance and highly appreciate your support.

B/regards
Anuruddha