My reflex is to sign off on this as mass stupidity, but that's probably not the correct take. A Christian living in a Christian area has no particular reason to learn about other religions, they're not planning to convert and they don't interact with people of other religions much, and when they do they quite rightly expect that person to explain any important matters. "I won't be here that day, its a holy day", as opposed to getting offended "What do you mean you don't know Paryushana was yesterday?" in general Jains in western culture are expected to point out 'That's not a Swastika, I'm not a Nazi' rather than expect people to guess. Lots of people do live in melting pot areas, or undergo a 'spiritual grazing' phase in life, and learn this stuff, because its relevant, and some of us just seem destined to go through life winning every game of Trivial Pursuit and being 'that person' who says stuff like "Actually, the.." and "Contrary to Popular belief..."

Lots of these quizzes show false ignorance too, people know stuff in context and to the degree needed. Multiple choice helps because it gives a correct answer to stir the memory, but a lot of times all you need to know is "Caw-ran, muslim thingy", most people don't read the daily newspaper, might not have seen it, or seen it spelled Quran, Koran, Qu'ran etc, I'd bet most of the people who missed that, if you said "Its their primary religious text" would nod their heads, unsurprised. Always get weird answers off quizzes anyway, as I'm sure you know, I remember giving a pop quiz once material I'd just covered, and even repeating the answers to all of them in the summary before handing it out, and people still got some wrong, I asked a student afterwards, "Why'd you think the Moon exerts less force on the Earth? I know I repeated specifically that they were equal" and got "Yeah, I remembered, but you said tides were caused by unequal forces on the Earth from the moon" Not quite what I'd said, but ironically, her being mostly right about two things made her get it wrong when a less right person would have got it right. Ask random people what a thermometer measures and they'll say temperature, ask students a couple months into a physics class and a big chunk of them will say heat instead, it wouldn't really be right to describe them as more ignorant then those who never took the class.