Pertaining to the risk factors for ischemic heart disease (IHD), which of the following statements is correct?

a.Men are at increased risk of IHD due to increased lifetime oestrogen production.
b.The elderly are at lower risk of myocardial infarction, partially due to reduced atherosclerosis progression.
c.Unstable angina is a greater risk factor for Myocardial Infarction than stable angina.
d.Smoking, diabetes and hypertension are protective against the development of IHD.
e.Atherosclerosis in the right ventricle is a major risk factor.