4. Agrobacterium-mediated T-DNA delivery of CRISPR/Cas9 expression cassettesis an advanced tool for genome editing in plants. Which of the following descriptionsabout this technique is not correct?
(A) Only the T-DNA region is transferred from agrobacterium into the host plant'snuclear DNA genome.
(B) The virulence region of the Ti plasmid encodes proteins to form a membrane-spanning DNA transporter called the type IV secretion system (T4SS).
(C) CRISPR/Cas9 cleaves foreign DNA via two components, Cas9 and sgRNA.
(D) The sgRNA is a synthetic RNA containing a 5'-end with a 20-nt sequence thatacts as a guide sequence to identify the target sequence accompanied by a protospaceradjacent motif (PAM) sequence.
(E) When a template is present, nonhomologous end-joining (NHEJ) can beactivated and results in gene replacement or knock-in.