MikTeX comes with 69 languages preloaded as reported at compilation time:
This is XeTeX, Version 3.14159265-2.6-0.99992 (MiKTeX 2.9 64-bit) (preloaded format=xelatex 2015.11.9) 13 NOV 2015 10:35 entering extended mode **PlasmaBook1.tex ("D:\Your files\KIA\OneDrive\PlasmaBook2\PlasmaBook1.tex" LaTeX2e <2015/01/01> patch level 2 Babel <3.9m> and hyphenation patterns for 69 languages loaded.
I don't like this situation while cannot explain exactly why, perhaps, because in the past saving computer memory was a recommended practise.
I tried to remove unused languages though the MikTeX Options.
and rebuilt all formats:
Nothing has changed. At compilation time I still saw
Babel <3.9m> and hyphenation patterns for 69 languages loaded.
initexmf --dump from command prompt has actually removed unused languages. It seems that MikTeX Options has long-standing bug as was reported in Language (hyphenation patterns) not available 2 years ago.
A minor question is which of 4 hyphenation patterns for German language available in MiKTeX is recommended for users who (as me) load German pattern only to cite references.