How do you categorize a question on yahoo answers?

It's reversed now. IF you use relevant keywords in your question, when you submit it, it will be placed automatically in the correct category/subcategory. If it lands in the wrong spot, you can select Edit>Edit category AFTER you've posted the question, and move it to where it belongs. You can no longer select your category before you post (that ended years ago). 

If you post a question go to your question, click 'Edit' and then select 'Edit Category'. You will see a list of categories and can move it where you want it.

We haven't been able to do that since 2013, 7 YEARS AGO. Questions?are automatically categorized by the server computers from keywords in your question. If the question posts in the wrong category and subcategory, you need to to left click or tap either the "Edit" hyperlink then the "Edit category" option or the pencil icon to the right of the?question to move the?question. 

Whining about Yahoo or YA have gone downhill gets you nowhere. Verizon BOUGHT Yahoo 4 YEARS ago. That is HISTORY. It is time to MOVE ON or leave YA for good. Go exploit the Reddit communities instead.

Pagan user Shadowfire from Portland (or so he claims) has many trolls accounts on Yahoo Answers: Blackthorne1979, Carter Berg, Fireball, ThatToiletguy, Reynaldo Weeks, Petri Lindroos, Knightwulf, Toilet John, Master Debator, Magistra, D-girl, Firecock, Yahoo User, Corvus Blackthorne, Shadowfire the Sarcastic, Shadowfire Lives, Shadowfire Lives bythches, etc. and any other anonymous accounts. With one his accounts Fireball, he pretends to be a Methodist old lady who posts short-hand slang TIRH (this is religion here). He reports all answers and questions that he doesn't like just so that his questions stay on top in the Religion and Spirituality section. He trolls in other categories too. It gives Christians a bad name (just because of this troll's sock puppet account). His Toilet John account keeps posting questions where Jesus was sodomized by Roman soldiers. He asks multiple idiotic mundane questions and answers them with his sock puppet accounts just to gain points. With his Reynaldo Weeks account he boasts that he was the reason why their accounts were suspended. With his Magistra account he threatens people with clowns and CIA assassins. Shadowfire mocks Christians with his sock puppet account Fireball in the Religion and Spirituality section by answering very destructively and adding "TIRH here" or reported (anonymously) or “fck you nigers”. He gives Christians a bad name because he promotes sins like sodomy, fornication, ecumenism, astrology (horoscopes), etc. He should be executed and burned at the stake for blasphemy. He spreads rapture heresy, ecumenism heresy, etc. and many more subtle heresies. Antichrist will ride on a donkey into the 3rd Temple. Stop him before it’s too late.

you cant before the question is posted after its posted you can pick it before you post it yahoo will try and guess what category to place it in based on key words used in your question if its not placed correctly you can move it to move it go to your question under the blue edit menu click on edit category then select the new category to put it in then click submit