6.Which of the following statement is NOT correct for the evaluation of SARS-CoV-2 infection?(A) Lower Ct (threshold cycle) value represents the higher titer of the virus.(B) Genomic RNA should be converted to cDNA before polymerase chain reaction for the quantitation of virus titers.(C) Identification of SARS-CoV-2 variant and sequences is critical to judge the cross-contamination.(D) Amicron variant contains more mutations compared to delta variant.(E) mRNA of the nucleocapsid protein is currently used for the vaccination.