Finally,()weareswitchingtoanewcoupon-basedsystem,wewillbediscontinuingtheuseofcustomerrewardcards.Reassurecustomersthattheycanredeempointsuntiltheendoftheyear.Explaintocustomersthatthecouponsystemwillprovidegreatersavings. Ifacustomerhasanyfurtherquestions,pleasereferhimorhertothemanageronduty. Thankyouforyourhardworkinrecentweeks. Sincerely, Greg A.although B.unless
A.正确答案D
B.so C.
D.because
