Identify the correct statement w.r.t. capping.

Almost all eukaryotic pre-mRNAs are modified at their 5' ends by the addition of a structure called a 5' cap. This capping consists of the addition of an extra nucleotide at the 5' end of the mRNA and methylation by the addition of a methyl group (CH3) to the base in the newly added nucleotide and to the 2' –OH group of the sugar of one or more nucleotides at the 5' end.