$8.8.$ In Canada, which of the following is true regarding screening candidates for substance abuse?Oa$.$ Employers are always permitted to screen candidates for substance abuse if they choose to do so$.$ b$.$ Employers are only permitted to screen candidates for substance abuse if the substance that they are abusing is illegal. c$.$ Employers are only permitted to screen candidates for substance abuse if the substance that they are abusing is legal. d$.$ Alcohol and drug addiction is considered to be a disability under human rights codes. e$.$ It is often acceptable to discriminate against candidates during the selection process when that discrimination is based on alcohol or drug addiction.