Descartamos una respuesta del cuestionario.

Descartamos is the 1st person plural form of descartar — so the subject is we.

A useful thing to know is that descartamos can mean either:

• we discard / we rule out (present tense), or
• we discarded (preterite)

These two forms look exactly the same for -ar verbs in nosotros/nosotras.

So without more context, the sentence could be understood as either:

• We discard a response from the questionnaire
• We discarded a response from the questionnaire

Context normally makes it clear.

Spanish often leaves out subject pronouns when they are not needed.

Since descartamos already tells you the subject is we, adding nosotros would usually be unnecessary:

• Descartamos una respuesta del cuestionario.
• Nosotros descartamos una respuesta del cuestionario.

Both are possible, but the version without the pronoun is more natural in many situations.

You might include nosotros only for emphasis or contrast, for example:

• Nosotros descartamos una respuesta, pero ellos no.

Una is the indefinite article: a / an.
It suggests that the sentence is talking about one response, but not a specifically identified one.

• una respuesta = a response
• la respuesta = the response

So:

• Descartamos una respuesta del cuestionario = we discarded one response from the questionnaire
• Descartamos la respuesta del cuestionario = we discarded the response from the questionnaire

A learner should also notice that respuesta is feminine singular, so the article is una.

Because in Spanish, de + el contracts to del.

So:

• de + el cuestionario → del cuestionario

This is a standard contraction and you should normally always use it.

Examples:

• el título del libro
• una página del periódico
• una respuesta del cuestionario

But this only happens with el, not with la:

• de la encuesta ✅
• dela encuesta ❌

Here, del cuestionario most naturally describes respuesta.

So the structure is basically:

• Descartamos = we discard / we discarded
• una respuesta = a response
• del cuestionario = from the questionnaire / on the questionnaire

In other words, it means:

• a response from the questionnaire
• a questionnaire response

So del cuestionario is telling you what kind of response it is.

Because respuesta is a thing, not a person.

The personal a is mainly used with specific human direct objects:

• Veo a María.
• Ayudamos a los estudiantes.

But with things, you usually do not use it:

• Descartamos una respuesta.
• Compré un libro.
• Analizamos los datos.

So in your sentence, una respuesta is a direct object, but it does not take the personal a.

Yes, respuesta is feminine:

• una respuesta
• la respuesta

A common learner mistake is to assume that words ending in -a are always feminine and words ending in -o are always masculine. That pattern is very common, but what really tells you the gender here is the article:

• una respuesta → feminine
• el cuestionario → masculine

So in this sentence you can clearly see:

• respuesta = feminine
• cuestionario = masculine

Cuestionario is a masculine singular noun meaning questionnaire.

That is why the sentence uses:

• el cuestionario
• del cuestionario = de + el cuestionario

So if you wanted to talk about more than one questionnaire, you would say:

• el cuestionario → the questionnaire
• los cuestionarios → the questionnaires

Yes. Descartar is often used in Spanish for several related ideas, such as:

• to discard
• to reject
• to rule out
• to eliminate from consideration

So depending on context, Descartamos una respuesta del cuestionario could sound like:

• we discarded a response
• we rejected a response
• we ruled out a response

In survey, testing, or data-analysis contexts, discarded or ruled out are often very natural translations.

The natural stress is:

• descartamos → des-car-TA-mos
• cuestionario → cues-tio-NA-rio

Neither word needs a written accent mark because they follow normal Spanish stress rules.

This matters because English speakers sometimes want to stress the wrong syllable, especially in longer words like cuestionario.

Yes, but the given order is the most neutral and natural.

Standard order here is:

• Descartamos una respuesta del cuestionario.

You might also hear other orders for emphasis, but they are less neutral:

• Una respuesta del cuestionario la descartamos.
  This puts special emphasis on una respuesta del cuestionario.

For most learners, the safest pattern is:

• verb + object + modifier

So the original sentence is a very good normal model.