Hoặc
Chọn D
Ta có
C20190+C20191+C20192+C20193+...+C20192016+C20192017+C20192018+C20192019=22019
⇔C20190+C20191+C20192+C20193+...+C20192016+C20192017+C20192018+C20192019=22019−C20192018−C20192019
⇔C20190+C20191+C20192+C20193+...+C20192016+C20192017+C20192018+C20192019=22019−2019−1