Using the NeoR/Tk System of Introducing Gene Replacements into Mice

Multiple Choice

Using the NeoR/Tk system of introducing gene replacements into mice (as described in the text) , which of the following gene combinations would identify those mouse cells that were the result of homologous recombination?

A) NeoR only
B) Tk only
C) NeoR and Tk
D) Neither NeoR or Tk