Which of the following is not  a cloning vector? 

A probe is a short stretch of single stranded, labelled nucleotide molecule complementary to the target nucleotide sequence. Probes are used to identify the gene of interest by hybridisation techniques.

(2) and (3) A vector is a vehicle DNA molecule that carries a gene of interest into a host cell and facilitates its stable replication and inheritance. Naturally occurring bacterial plasmids were used as vectors initially.

BAC and YAC are also artificial vectors that are specifically designed to carry larger DNA fragments of size 100–1000 kbp. Since these are much longer DNA molecules, their structure is designed to resemble a 
chromosome for stability. Thus, they are named bacterial artificial chromosome and yeast artificial chromosome, suitable for bacterial (prokaryotic) host and eukaryotic host, respectively.

(4) pBR 322 is an artificially designed E. coli based plasmid vector that can carry a DNA molecule up to a size of 10 kb.