Choose the best sentence after changing the highlighted word/phrase (simple infinitive) into gerund.

Sentence - The thing to establish first is what is actually a secret, what is to be suppressed, if one is to avoid damage to self or another.

Establishing what actually a secret is, what is to be suppressed first, is necessary to avoid damage to self or another.

Establishing what actually is a secret, what is to be suppressed first, is necessary to avoid damage to self or another.

Establishing what actually is a secret, what is to be suppressed first, is necessary to avoiding damage to self or another.

Establishing what actually are a secret, what is to be suppressed first, is necessary to avoid damage to self or another.

Establishing what actually is a secret, what is to be suppressing first, is necessary to avoid damage to self or another.