It is indeed.
You can delete a question by using the blue "Edit" up to the point that there is an answer to the question.
As per the help pages:
Changes to your question or answer
After posting an answer, feel free to edit or delete it up until the Asker chooses a Best Answer. A question can only be deleted before it receives its first answer.
The latest link from Yahoo help of the subject follows:
https://help.yahoo.com/kb/answers/question-answer-sln4198.html?impressions=true