A questions asks why Mary is prominent in Islam? Mary is an important person in her own right and has a prominent place in the religion.
The message of the Quran was shown to be in harmony with the message of the previous prophets. Islam and the Quran were shown to be a natural continuation of the messages, which were once delivered by Abraham, Moses and Jesus.
Mary had a great importance in Christianity so the Quran, in appealing to people, would make prominent mention of her in the Quran.
In the Quran, we see that the angels announced to Mary that God has chosen her and preferred her to be above all of the women in the world.