The answer is c.
When you look at the data, in the first column, the frequency of sales of both are similar. Even the second column shows similar data. Association is determined if there is a significant difference between the data in each column/row depending on what you are aiming to answer.
In this case, we look at it per column because you want to compare the frequencies of sales of each company which are aligned by columns. So we know to look at the columns and not the rows.
