Answer:
b. the top row of a table that shows titles for the cells below
Step-by-step explanation:
A header row is the first row of a given table that shows titles of the cells below it. In many cases, the header row has different styles from the other rows in the table. A header row can be found in, among others, both Microsoft's Excel and Word applications.
In the attached figure, the first row with a darker shade of background color is the header row for the table.