What are the net electric charges on DNA and histone proteins?

Negative and positive.

The correct answer is Option (3)- Negative and positive.

DNA has a negative charge due to its phosphate backbone, which carries negatively charged phosphate groups. Histone proteins, on the other hand, are positively charged because they contain a high proportion of positively charged amino acids like lysine and arginine.

This difference in charge facilitates the binding of DNA to histones, allowing the DNA to wrap around the histones and form nucleosomes, which help in the compact packaging of DNA within the cell nucleus.