Which photo should I use in a marriage biodata?

The photo decides whether anyone reads the rest of the page, so take it seriously.

Use a photo that is:

• Recent, taken within the last year
• Clear on the face, shot in daylight or good natural light
• On a plain or simple background, not a crowded function hall
• Solo, not cropped out of a group photo where someone's hand is still on your shoulder
• In decent traditional or formal wear, with a natural smile

Avoid heavy filters, sunglasses, mirror selfies, gym pics, and photos from your cousin's wedding where you are one of eleven people.

Two photos are ideal: one clear portrait and one full length. That is enough.