The blood taking time of oral glucose tolerance test (OGTT) is ( )
A.
0h, 0.5h, 1h, 2h after oral glucose
B.
0.5h, 1h, 2h, 3h after oral glucose
C.
0.5h, 1h, 2h, 4h after oral glucose
D.
1h, 1.5h, 2h, 2.5h after oral glucose
E.
1h, 1.5h, 2h, 4h after oral glucose