Which of the following acts as a vector?

Which of the following statements are not true regarding restriction endonucleases?
$A$. They are called molecular scissors.
$B$. These are the enzymes responsible for restricting the growth of bacteriophages in $E. coli$.
$C$. They cut the $DNA$ only at the centre of the palindromic sites.
$D$. They remove nucleotides only from the ends of $DNA$ fragments.
$E$. They recognise specific palindromic base-pair sequences.
Choose the answer from the options given below:

In genetic engineering,the reason for using restriction endonucleases is that ...

The key tools required for the recombinant $DNA$ technology are:
$I.$ Enzymes
$II.$ $RNA$ primer
$III.$ $DNA$ probe
$IV.$ Vectors
$V.$ Host organisms
Select the correct option.

Using recombinant technology,genes from a donor cell can be transplanted into a bacterium for $DNA$ replication and protein synthesis. The kinds of cells that can be used as a donor in this technology are

Which enzyme is used as molecular scissors?