Only high IQ knows which room the pregnant woman is in

You observe three women in three different rooms, one of them is pregnant. How can you pinpoint this woman without wasting too much time?

The answer will show your IQ! Smart people easily overcome this challenge, how about you?

Which woman is pregnant?

Please fill in the answer to the above puzzle in the comment box below. By answering correctly, you have successfully joined the top 10% of people with high IQ. Don't miss the opportunity to prove yourself with this challenge!

NHI NHI

Source: https://vtc.vn/iq-cao-moi-biet-nguoi-phu-nu-mang-thai-dang-o-can-phong-nao-ar816936.html