Final answer:
The correct answers are TALEN and Zinc finger nucleases (ZFN), which are genome editing tools that use a protein domain fused to a nonspecific nuclease for targeted DNA modification.
Step-by-step explanation:
The question revolves around the identification of a genetic engineering tool in which a protein is fused to a nonspecific nuclease domain. The correct answer to this is neither RNA polymerase nor Casper (which seems to be a typo and likely refers to CRISPR-Cas systems), but rather the genome editing tools known as TALEN (Transcription Activator-Like Effector Nuclease) or Zinc finger nucleases (ZFN). Both are designed to target and modify specific DNA sequences within a genome using programmable, sequence-specific DNA-binding domains that are fused to a nuclease, which can induce double-stranded breaks.