请选择ABC)D3Y4i/z8B2J3y'_2O*uThe first day of a week is_______ .4I8R3W1i,C9D5u)~/v2G(X+c8r
A. Monday4I8R3W1i,C9D5u)~/v2G(X+c8r
B. Sunday4I8R3W1i,C9D5u)~/v2G(X+c8r
C. Saturday4I8R3W1i,C9D5u)~/v2G(X+c8r