To me (A sounding grammatically correct, but more naturally “… a difficult business.”), B should be extended to shift an emphasis on the skyscraper under construction, eg Sandy soil\high water level makes the construction of the skyscraper extremely difficult. OR: What makes the construction of the skyscraper difficult is…
I meant to say using ‘the’ in a standalone sentence, out of context, sounds unnatural to my ear. I would expect something preceding this sentence which could clarify why we refer to it as a something specific. Eg Planning is easy. The construction of a skyscraper is difficult.
But for a person whose language doesn’t have articles, you have to be raised among them to thoroughly understand the thing. Second nature as they say.
Construction of a skyscraper (skyscrapers) is difficult. (General)
The construction of a skyscraper (skyscrapers) is difficult. (The semantic emphasis, to me, is on skyscrapers because it could mean the construction of other things like a multi-storeyed building/a bridge/a highway may not be as difficult)
— Thank you Anglophile.
Can I say “the construction of a skyscraper” in B means either constructing a skyscraper specified by something preceding or postposing it as Eugene2114 says, or constructing a skyscraper not a multi-storeyed building/a bridge/a highway as you say?
Perhaps, Eugene looks at it from the angle of the general use of the definite article. But I’d imagine that you are discussing various types of civil work and then you say that the construction of a skyscraper is difficult (as compared to other types of construction, probably). However, the real context will determine which of the two views is more acceptable.