Read the following passage carefully and answer the questions on it.

      We have often heard students making wild assertions that the public examining bodies are their worst enemies. Some, in fact, see the officials of these public examining bodies as wicked souls scheming day and night to devise ways of failing them. How correct are these assertions? The facts will speak for themselves. 
      The task of setting an examination paper begins long before the examination day. Indeed. months or years before then, seasoned experts in the-various subjects are given the teaching and examination syllabuses and requested to set questions. These are compiled for subsequent scrutiny. Then a second set of experts is invited to examine the questions critically, make necessary modifications and come up with questions that conform with acceptable standards. The result of this exercise is a set of polished and unambiguous questions that are very fair to those being examined. These questions are then securely stored. 
      The next stage is the registration of candidates This stage involves not just the examining body, but also the candidates, their parents. their teachers. principals and some other members of the public. This is so because apart from the candidate having to fill in the forms. his principal has to endorse them while the parents have to provide the registration fee. Any mistake or inaction on the part of any of these may ruin the candidates chances. If, for instance, the candidate makes a mistake in his choice of subjects or in completing his forms or if the principal does not forward the registration fee at the right time. his chances in the examination may be jeopardized. 
      Next is the conduct of the examination itself. Again. more officials from outside the examining body than from within it are involved. Think of the supervisors. the invigilators, and even the security officials. They are definitely more in number than the staff of the examining body and any one of them could take an action that might result in the failure of candidates. Take the invigilator for instance If he is negligent candidates could swap answer scripts under his very nose; and when this is detected by the markers, as it often is. the results of the candidates may be cancelled. 
      Probably, the most hated person to the candidates is the marker whom they, in their ignorance, regard as a wicked drunkard who delights in failing candidates. What candidates do not realize is that an examiner is trained to score points strictly according to a carefully prepared marking scheme from which he must not deviate it is his constitution. Besides, his work is consistently checked by his team leader and the chief examiner. Should he be discovered to have marked inaccurately, he could be removed. So, contrary to candidates' opinion. the examiner is a seasoned teacher, a careful scorer, a person always on his guard. 
      The final stage comes with the collation of results. This stage is mainly computerized, and computers do not make mistakes. A candidate's results may not be processed if he is involved in a malpractice, has used a wrong examination number or no number at all, or if he fails to write all the papers that make up a subject. So. when a result is withheld, the fault is mostly that of the candidate.
      How then should we view the activities of the public examining bodies? Definitely, we should view them with understanding, sympathy and appreciation. 
(a) In one sentence, summarize the writer's purpose in this passage. 
(b) In two sentences, one for each, state how the actions of the candidate and the invigilator can jeopardize the candidate's chances of success. 
(c) In three sentences, one for each summarize the steps taken by examining bodies to ensure that candidates are given a fair chance of success.