A、<span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">降低</span>
B、提高
C、<span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">不改变 </span>
D、<span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">未知</span>
A、<span style="FONT-FAMILY: 宋体; mso-ascii-font-family: \'Times New Roman\'; mso-hansi-font-family: \'Times New Roman\'">降低</span>
C、<span style="FONT-FAMILY: 宋体; mso-ascii-font-family: \'Times New Roman\'; mso-hansi-font-family: \'Times New Roman\'">不改变 </span>
D、<span style="FONT-FAMILY: 宋体; mso-ascii-font-family: \'Times New Roman\'; mso-hansi-font-family: \'Times New Roman\'">未知</span>