According to the passage，a great variety of influenza strains can appear when______.A. H and N spikes are producedB. animal and bird viruses are combinedC. dissimilar types virus recombineD. two viruses of the same type are contracted
According to the passage，a great variety of influenza strains can appear when______.
A. H and N spikes are produced
B. animal and bird viruses are combined
C. dissimilar types virus recombine
D. two viruses of the same type are contracted
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大众车系睡眠模式下总线电压：CAN-L为5V，CAN-H为0V。