Answer:
option 3
Step-by-step explanation:
In non-homologous end joining, the break ends are directly ligated together without the need for a homologous template unlike the homologous repair. this form of repair uses short homologous sequences of DNA termed microhomologies to direct repair and these microhomologies are seen as single-stranded overhangs found on the ends of double-strand breaks. When the overhangs are perfectly compatible, NHEJ ligates and repair the break. When these overhangs are not compatible, imprecise repair leading to deletion of nucleotides can also occur which is much more common .