Sometimes i might not answer the questions in a clear form.And so if someother person gives the brief and clear answer.I would like to delete my own answer,so that the post might contain the most relevant answer which is useful for all other users to get the right answer.But when i click delete,the answer is not deleted instead it show's a undelete option.Why??
The answer is indeed deleted. However, this site is part-wiki so things are never truly deleted. Owners of the content (Like yourself) and certain privileged users can view deleted questions and answers.
The fact that you;re seeing an undelete options means the content was removed from public viewing for that post.