Final answer:
Histone H2B is one of the scaffolding proteins involved in chromatin remodeling. It binds to acetylated histone tails and has histone acetylase activity, promoting transcription.
Step-by-step explanation:
Histone H2B is one of the scaffolding proteins involved in chromatin remodeling. It binds to acetylated histone tails and has histone acetylase activity, which promotes transcription. Histone acetylation results in the loose packing of nucleosomes, allowing the DNA to be accessible for transcription. This process is catalyzed by histone acetyltransferases (HAT enzymes). By acetylating lysines near the amino end of histones H2B and H4, histone H2B helps unwind nucleosomes and open the underlying DNA for transcription. Therefore, the correct answer is option 3) Histone H2B.