Answer:
The correct answer is: a. Write a catchy and targeted subject line.
Step-by-step explanation:
In an e-mail sales message it is important to write a catchy and targeted subject line as that is the first thing the recipient would see when they receive the email. While it is cliche to say "first impressions matter", this is very true when it comes to sales.
Target customers might receive several sales messages via email daily, many of which are ignored and not even opened by them. To make your sales message something customers open and read in the first place, it is important to have a catchy and targeted subject line so it hooks the recipient and makes them want to open it to read more about it.
Option B is incorrect as it does not even guarantee that your email will be opened, let alone the recipient would read the email till the very end.
Option C is important, but not as important as option A.
Option D is unhelpful as it does not evoke a lack of urgency in customers that serves well in making them purchase your product/ service.