Can someone explain this "los" versus "las" question

Question

I am doing an online test and was asked to translate: "I am going to eliminate them slowly."

I put: "Voy a eliminarlos lentamente."

The answer was marked as incorrect and two alternative correct answers were supplied:

"Voy a eliminarlas lentamente."

"Los voy a eliminar lentamente."

I thought that you used Las if the objects were feminine and Los if they were masculine so I am not sure why my answer could not have been correct. Would appreciate it if someone could explain where I have gone wrong. (There was no other information supplied i.e. it was just a random single sentence.)

Answer 1

In my opinion, given no antecedent, you have all four options:

Los voy a eliminar lentamente.

Las voy a eliminar lentamente.

Voy a eliminarlos lentamente.

Voy a eliminarlas lentamente.

It is interesting that they would only allow one of the masculine antecedent options and one feminine. But that does show that you were not missing a referent. I think someone just failed to program all the possibilities.

Just my opinion, but I see nothing wrong with your answer, and no lapse in knowledge.

I use Duolingo, which has similar computer graded answers and I don't think they have ever failed me on gender- they have on other things- word choice etc. that I think I was right on- but they have comments where people leave opinions and I can look and see if anyone agreed with me.

Thanks. There have been others where I couldn't see my error (other than US vs UK English at times) but this I wasn't sure if I had correct or not. Thanks for your help. - ErikainAndalusia, Jun 14, 2016

It was Duo-lingo - ErikainAndalusia, Jun 14, 2016

Answer 2

Eliminar las preguntas. "Preguntas" is feminine so it depends on what you were going to eliminate slowly.