Apple manufactures all their own devices. They don't have any incentive to do so nor any way to do so since they're not dealing with 3rd party phone manufacturers.
A) I disagree. Apple's incentive is in getting people to pay top dollar to live in the Apple ecosystem. They require a certain level of trust. Selling out people's data to Facebook does not achieve that end. The risk of getting caught is far higher than the reward from those analytics.
B) Apple controls the entire supply chain for iPhones. They have no need from a profit standpoint to try and insert hardware that allows other companies to do anything to their users. The secret backdoors are almost always the result of some exchange - FB offers data about users in exchange for the ability to insert hardware/software into a phone. Since that exchange doesn't exist for Apple, there's no reason for it.
My apologies for being unclear. Yes, it is known that FB can and has taken a ton of info from Android. I was questioning how they know that Apple doesn't put in back doors, and doesn't spy on you.