I agree with b) and c). A is a bit forced though as tobacco companies faked studies to show that what they sell is healthy even though they knew it was horribly bad for you, I don't see how Google is anything like that with respect to hiring processes. If they talked about ads or search then the likeness would make sense, but I don't see it for hiring.
But I agree that Google is different than most companies. There the main thing is ads and search and infrastructure to run both of those. They can always use more developers to help optimize the profits of those algorithms or reduce runtime costs, the ROI on that is extremely high so that is what their hiring process is optimized for. Some of their other projects might have done better with a different process, but they don't have much weight compared to the revenue generating projects.