Questions & Answers about A vossa ajuda é muito útil para elas.
Why do we use elas after para? Can't we use an object pronoun like lhes?
Does vossa mean that the people we are talking to are all female?
Why is there an A before vossa ajuda?
In European Portuguese, it is standard practice to put a definite article (o, a, os, as) before a possessive word. Because ajuda is a feminine singular noun, we use A before vossa. You can think of it literally as meaning The your help.
Since the help is for elas (them), shouldn't the adjective be plural, like úteis?