How does a togavirus ensure that only full length genomes are packaged into the virions?

A) Only full length genomes will fit into the capsid.
B) Only full length genomes are produced near the site of assembly.
C) Only full length genomes can bind to the envelope glycoproteins.
D) Only full length genomes contain the packaging signal.
E) Only full length genomes can be processed by the viral nuclease.