No, ethanol is a solvent here. Alcohols are not very acidic, they have pka 16, which is a weak acid. Ethanol is not strong enough to protonate epoxide and make a carbocation. Therefore, in this reaction base attacks the least subbed site. Hope this helps.
Dude I thought the same thing, I thought the OR- was the nucleophile, but regardless, I got the question right because a strong nucleophile, will attack a ring on the least substituted side because of backside attack. Like Grignards for example, although now that I think about it, I'm pretty sure you can only put Grignards in base since an acid would react with the Grignard. Now I'm just confused 🙁 I'm pretty sure I've seen a strong nucleophile in acid attack the least sterically hindered side because of backside attack.
