Read the following statements regarding the features of cloning vectors: (A) The 'ori' sequence is responsible for controlling the copy number of the linked DNA. (B) A cloning vector must have multiple recognition sites for a single restriction enzyme to ensure successful integration of alien DNA. (C) Selectable markers help in identifying and eliminating non-transformants and selectively permitting the growth of the

Step-by-step solution

Statement (A) is correct because the origin of replication (ori) is the sequence where replication starts, and it also controls the copy number of the linked DNA. Statement (B) is incorrect because a cloning vector needs to have very few, preferably single, recognition sites for commonly used restriction enzymes. The presence of more than one recognition site within the vector will generate several fragments, which complicates the gene cloning process. Statement (C) is correct as selectable markers are essential to