Choose the best answer

It is acknowledged that Vietnam had a complete control over SARS from a very early stage of the epidemic.A. 
Vietnam is acknowledged to have completely controlled SARS from a very early stage of the epidemic.
B. 
Vietnam is acknowledged to have controlled SARS from a very early stage of the epidemic.
C. 
Vietnam was acknowledged to have had a complete control over SARS from a very early stage of the epidemic.
D. 
Vietnam is acknowledged to have a complete control over SARS from a very early stage of the epidemic.
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