Answer: (A) Market share
Explanation:
Market share is one of the concept that helps in understanding the overall percentage of the sales, productivity of the industry over the specific period of time.
The market share is one of the important business concept that helps in calculating the overall sales of the products and the services and categorized based on the specific brands in an organization.
According to the given question, the marketing manager of the company basically assessing their progress against the competitor rivals and also tracking the specific portion of the overall computer tablets sales.
Therefore, Option (A) is correct answer.