Which is the most efficient way to avoid dna mutations from uv radiation?
avoid getting x-rays at the doctor’s office.
avoid protective shields during x-rays.
avoid uv radiation by wearing sunscreen.
avoid uv radiation by using a tanning bed.

Sunscreen is the best, and most efficient way to avoid DNA mutations. UV radiation causes thymine dimers in the DNA complex, so limiting UV radiation is key to avoiding DNA mutations.
X-rays are not good for you, but they are usually necessary.
Avoiding protective shields would increase the damage done by x-rays.
Using a tanning bed would also increase UV radiation damage. 

Ifound this on google “concept 13: meiosis ii: telophase ii. a nuclear envelope forms around each set of chromosomes and cytokinesis occurs, producing four daughter cells, each with a haploid set of chromosomes. a nuclear envelope forms around each set of chromosomes.” i hope this you for what your looking for.