A、<span style="font-size: 16.8px; background-color: rgb(255, 255, 255);">U</span><span style="font-size: 12.6px; line-height: 0; position: relative; vertical-align: baseline; bottom: -0.25em; background-color: rgb(255, 255, 255);">N</span><span style="font-size: 16.8px; background-color: rgb(255, 255, 255);">I</span><span style="font-size: 12.6px; line-height: 0; position: relative; vertical-align: baseline; bottom: -0.25em; background-color: rgb(255, 255, 255);">N</span>

B、<span style="font-size: 16.8px; background-color: rgb(255, 255, 255);">U</span><span style="font-size: 12.6px; line-height: 0; position: relative; vertical-align: baseline; bottom: -0.25em; background-color: rgb(255, 255, 255);">N</span><span style="font-size: 16.8px; background-color: rgb(255, 255, 255);">I</span><span style="font-size: 12.6px; line-height: 0; position: relative; vertical-align: baseline; bottom: -0.25em; background-color: rgb(255, 255, 255);">N</span><span style="font-size: 16.8px; background-color: rgb(255, 255, 255);">/η</span><span style="font-size: 12.6px; line-height: 0; position: relative; vertical-align: baseline; bottom: -0.25em; background-color: rgb(255, 255, 255);">N</span>

C、<span style="font-size: 16.8px; background-color: rgb(255, 255, 255);">U</span><span style="font-size: 12.6px; line-height: 0; position: relative; vertical-align: baseline; bottom: -0.25em; background-color: rgb(255, 255, 255);">N</span><span style="font-size: 16.8px; background-color: rgb(255, 255, 255);">I</span><span style="font-size: 12.6px; line-height: 0; position: relative; vertical-align: baseline; bottom: -0.25em; background-color: rgb(255, 255, 255);">N</span><span style="font-size: 16.8px; background-color: rgb(255, 255, 255);">η</span><span style="font-size: 12.6px; line-height: 0; position: relative; vertical-align: baseline; bottom: -0.25em; background-color: rgb(255, 255, 255);">N</span>

D、<span style="font-size: 16.8px; background-color: rgb(255, 255, 255);">以上都不正确</span>