The correct answer is: B) decreased chromatin condensation
Histone modifications which include phosphorylation, methylation, acetylation and their reverse processes are post-translational modifications that can regulate gene expression. Their effect depends on the amino acid (protein) that is modified, and the combination of the other modifications.
These modifications regulate gene expression by organizing the genome into active form-euchromatin, where DNA is accessible for transcription, or inactive-heterochromatin, where DNA is less accessible for transcription.