单选题 COMPANY'S MAIN PRODUCTS
Product Brand Date of Present
introduction volume of sales
Heaters A 1998 $79,000
B 1999 $82,000
Freezers C 1997 $79,936
D 2001 $88,000

A. B Brand Heaters were first put on the market in 2001．and now it has the biggest volume of sales．
B. D Brand Freezers were introduced to the market late but it has the biggest volume of sales．
C. Each product has two brands and with the same volume of sales．