The Following Events Are Involved in the Regulation of Erythrocyte

The following events are involved in the regulation of erythrocyte production.What is the correct sequence of these events starting with a decrease in blood oxygen content?
1) blood oxygen decreases
2) erythropoietin activated
3) erythrocytes combine with oxygen
4) kidneys release renal erythropoietic factor
5) erythrocyte production stimulated
6) blood oxygen increases

A) 1, 4, 2, 5, 3, 6
B) 1, 3, 4, 2, 5, 6
C) 1, 2, 5, 4, 3, 6
D) 1, 5, 4, 2, 3, 6
E) 1, 2, 4, 3, 5, 6