This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Replication, Subject name: Biochemistry
Enzyme that produces single strand nicks in DNA: 
Select and explain. 
A. DNA polymerase I, B. DNAase I, C. Polynucleotide kinase, D. l - exonuclease
B: DNAase I
Answer: B: DNAase I 
Explanation: Deoxyribonuclease I (DNAase I) Acts on single-stranded DNA, double-stranded DNA, and chromatin. Makes single stranded cuts in nearly any segment of DNA i.e. has low sequence specificity. Digest DNA that is not protected/not bound by protein, into its component deoxynucleotides. Used in DNA Foot Printing. E.g. (DNase I) nick the single strands of double-stranded DNA.