"The convenience store is over there."
All three are correct translations to the English sentence though, so you should get the question right regardless of which you picked?
You just have to learn which one to use in which scenario in real life, so maybe this question is a bit too lenient lol
Kochira/koko/kore/kono - near the speaker (e.g. here, this...)
Sochira/soko/sore/sono - near the listener (e.g. there, that...)
Achira/asoko/are/ano - not near the listener nor the speaker (e.g. there, over there, that, that over there...)
Dochira/doko/dore/dono - question (e.g. where/which...)
I don't know exactly what the other option means but I think it can mean something like "over there, across the road".
(Sorry I don't have a Japanese keyboard)
It is called the "ko, so, a, do" system. If you look that up, you'll find a pattern that repeats itself across a miriad of other "demonstrative" words in Japanese. So, kore, kono, kocchi, kochira, etc all belong to the "ko" set, which indicate "this" (near the speaker). All of the "so" are "that" (near the listener), and the "a" (far away from both listener and speaker). Google could probably offer a more depth description of how and when to use the though. Good luck! :)
This is an area where you can't just learn the words, you have to know about the culture. In Japanese, speech is speaker-centric. Locations are relative, and can be described as "here" near the speaker as with こちら, or "there by you" near the listener as with そちら, or can be "over there" away from both the speaker as well as the listener, as with あちら.
This is called the こ-そ-あ-ど series (sometimes also including the question form ど as in どちら which way). You need to know this set because it will come up frequently, like with "this thing" この or "that sort" あんな. There is an excellent article on it in JapaneseProfessor about demonstratives.
But "across" when you are facing the thing to be crossed, is also "over there".
I think the ambiguity in the English has been made on purpose, to make learners doubt and search the uses and meaning of those words in Japanese.
I myself felt very unconfident when that 向こう popped up, and so I clicked on the forum link to see the comments given on the phrase by more knowledgeable people.
You literally gave me "コンビニはあちらです" as the translation for "the convenience store is over there" in this very lesson. Then expected me to choose "向こう" over "あちら" here without ever teaching me "向こう."
I guess you succeeded in making me remember this... I'm so mad ill never forget this word.