E.g.,I decided to base the software for my startup on Windows instead of Linux.
Why Windows? One source for nearly everything in software I need except what I have to write, my favorite editor and scripting language, Knuth's TeX, and Firefox! So, I get Windows XP and now 7, Windows Server of whatever years, old copies of Office and PhotoDraw (good enough for my purposes), SQL Server, IIS (Web site front end), .NET, ASP.NET, ADO.NET, huge on-line Microsoft documentation, in most of the really important ways really well written, lots of books and fora, lots of expert users, and, surprisingly, if have a really good question, then some good on-line support from experts from Microsoft, for free.
For a compiled programming language on Windows it seemed that I had basically just two choices, C# and the .NET version of Visual Basic. So, which one? Well, first-cut, the two are nearly equivalent, that is, offer essentially the same access to the .NET Framework and the common language runtime (CLR). So, really, the main difference is just in syntactic sugar.
Well for the sugar part, C# seems to borrow the sparse, obscure, deliberately idiosyncratic syntax of C, and I don't like that, regard it as inefficient, for coding -- writing, reading, or teaching. Visual Basic has a more traditional flavor of sugar I like much better for writing, reading, and teaching. So, I selected Visual Basic.
For JS, ASP.NET writes a little for me, but so far for my Web pages and everything else I have yet to write a single line of JS.
For C, I've programmed in it and have a little of it from open source in my project and otherwise regard it as walking or riding a bicycle instead of driving a car.
SQL? Sure: I'm using SQL Server. But so far my SQL queries have all been quite simple. So, I've learned what SQL I needed but likely couldn't pass a good test on SQL. I have a plenty good enough background in the theory and intentions of relational database, e.g., from one of Ullman's books, and will dig into more complicated SQL statements as needed.
So, net, my software development is significant and doing just fine, but for that "quiz" I'd be lucky to get 10%. So, the quiz is not a good evaluation of everyone doing serious software!