In assessing whether the improvement in product sales can properly be attributed to the marketing strategy change, it would be most helpful to find out Has the number of unique visitors to the NutriShake online site increased substantially in the last two years?
Option B
Step-by-step explanation:
Two forms to do that are technically available
(1) You are directly selling to clients on the website
(2) You are selling by indirect website and handler.
For example, Amazon has a variety of other companies that sell their goods on the website of Amazon. The Amazon prices are almost the same as those of the retailers. If you are a buyer, are you going to buy Amazon goods or visit the website of the seller? I find it's more easy and time consuming to "pay by button" on Amazon.
The two strategies are different, and they cannot be interchangeable