HDV is a defective RNA virus ,which is the cause?
选项：

A:HDV must have the assistance of HBV or other liver - loving DNA virus in order to replicate, express antigens and cause liver damage
B:HDV must be assisted by HAV to replicate, express antigens and cause liver damage
C:HDV must be assisted by HEV to replicate, express antigens and cause liver damage
D: HDV-RNA cannot encode viral structural proteins