Task 1Marketing by e-mailing is on the increase. Compared to other media,e-mail messages areextremely cheap to send. With TV, you are spending on ad agencies and cable channels. Withprint ads, you are helping to keep newspapers and magazines alive. Direct mail costs more than＄600 per thousand pieces.With e-mail, there are almost no costs at all. Its low cost makes e-mailmarketing become the most cost-effective(划算的）advertising method available today.With TV, you do not know who is watching your ads. Even with direct mail, you cannot besure that your mail has been delivered, or that anyone reads it when it gets there. With e-mail,you know within 24 hours exactly which messages have been opened, by whom, what links theopeners clicked on(点击），and what part of your message was working.Because of electronic links, those who open your e-mails can do their own research:they canexplore and see any of the thousands of products that you sell. They can see the colors and sizes.They can,and they do,read ratings and reviews. They can put products in their shopping cartsand buy them.36. E-mail marketing has become the most cost-effective advertising method because______

A) it is of extremely low cost
B) it is a new marketing method
C) it is popular with young people
D) it is the best marketing method available