Luke 1:34
How will this be, Mary asked the angel, since I am a virgin? — Mary's question is the question of mechanism, not proof: she is not asking for a confirming sign (unlike Zechariah) but asking how the announced birth can occur given her virginal status. The I am a virgin (andra ou ginōskō, I do not know a man) specifies the problem she is identifying: the normal biological mechanism for conception is not present in her situation. The question is the question of faith seeking understanding, not the question of doubt seeking evidence.