A、<span style="font-size: 16.8px;">CO</span><span style="font-size: 13.3333px; line-height: 0; position: relative; vertical-align: baseline; bottom: -0.25em;">2</span>
B、<span style="font-size: 16.8px;">CH</span><span style="font-size: 13.3333px; line-height: 0; position: relative; vertical-align: baseline; bottom: -0.25em;">4</span>
C、<span style="font-size: 16.8px;">NH</span><span style="font-size: 13.3333px; line-height: 0; position: relative; vertical-align: baseline; bottom: -0.25em;">3</span>
D、<span style="font-size: 16.8px;">H</span><span style="font-size: 13.3333px; line-height: 0; position: relative; vertical-align: baseline; bottom: -0.25em;">2</span><span style="font-size: 16.8px;">S</span>