Read the following four statements $(1-4)$ and identify the two statements that contain mistakes:
$1.$ The first transgenic buffalo,Rosie,produced milk which was human alpha-lactalbumin enriched.
$2.$ Restriction enzymes are used in the isolation of $DNA$ from other macromolecules.
$3.$ Downstream processing is one of the steps of $R-DNA$ technology.
$4.$ Disarmed pathogen vectors are also used in the transfer of $R-DNA$ into the host.
Which are the two statements having mistakes?

• A
  Statement $2$ and $3$
• B
  Statement $3$ and $4$
• C
  Statement $1$ and $3$
• D
  Statement $1$ and $2$