There are some different types of question here: Is the conscience innate or developed? Should you follow the conscience? Is conscience the faculty of reason or the 'voice of God'?
To what extent is conscience vital when making moral decisions?
Critically assess the claim that the conscience is a reliable guide to ethical decision making. 
How convincing are Butler’s claims that people have an innate sense of right and wrong? 
‘For moral issues surrounding sex the demands of conscience override other ethical considerations.’ Discuss.
Critically assess the claim that conscience is the voice of reason. 
Assess the view that the conscience need not always be obeyed. 
The examiner reported:
Examiners noted a wide range of responses to the question, some very good. However, there was a tendency for some candidates to list (often not accurately) what they thought were the opinions of various scholars. Whilst this gained some credit, the key word in the question was “assess”. Many responses seemed to be a summary of all aspects surrounding conscience, seemingly using pre-prepared class notes, rather than focussing on the specific question asked. Such responses struggled to achieve more than a basic or satisfactory response.
Those responses which did “assess”, as the question required, generally did very well. Only responses which displayed appropriate evaluative and critical thinking accessed the top levels. Again, no obvious errors or misconceptions were noted.
This from June 2008 (sample answer);
Assess the view that conscience is not a reliable guide to ethical decision-making. 
This question is from June 2007:
Assess the view that conscience should always be obeyed. 
This question is from June 2005 (see a sample answer):
Assess the view that conscience is not the voice of God, but is learned. 
(taken from the OCR website)