In Norwegian the question is about liking strawberries in general, if you ask about one specific strawberry the question would be: 'Do you like the strawberry?' The same in Norwegian: 'Liker du jordbæret'. Learn the noun like this: et jordbær, jordbæret, flere jordbær, jordbærene (a-one stawberry, the strawberry, strawberries, the strawberries.
Because jordbær is a grammatically neuter noun (et jordbær), and in most cases those do not take the -er suffix in indefinite plural form.
So it's just:
et jordbær = A strawberry
jordbær = strawberrIES
jordbæret = THE strawberry
jordbærene (or, jordbæra) = THE strawberrIES
What I learned is that you don't add the -er suffix to monosyllabic neuter words and compound words with such a word at the end. Jordbær is a compound word (jord=soil, bær=berry), and bær is monosyllabic and neuter, so the plural is jordbær. The same goes for (post)kort ((post)card) or (råd)hus (town hall/house), but et hjørne (corner) -> hjørner and et menneske (man) -> mennesker, since they are not monosyllabic.