I think this also translates correctly;
Adorno el árbol de Navidad para que todos admirarlo mañana.
as an alternative to
Adorno el árbol de Navidad para que todos lo admiren mañana.
Two correct answers as choices in the original question unless hinted to use subjunctive
Hola Ian,
Your first sentence would be grammatically incorrect, I am afraid:
When using "para que" you need the subjunctive.
If the sentence were using the same subject, you could have used "para" (without que) followed by the infinitive, like this:
Adornamos el árbol de Navidad para (todos/todos nosotros) admirarlo mañana.
In both clauses the subject is "we".
But para + que doesn't admit the infinitive, only the subjunctive.
Saludos
Inma
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