HU NLHE, We are in the BB.

I heard/read that in GTO our cards/our range etc is more important than Villains. Thats the beauty of GTO. 

1)

So BTN opens for min, how much do we have to defend?

A) He invests 1,5 bb to win 1.5 bb. So we need to defend 50% to not give him an autoprofit on every open.

B) We have to call 1 to win 3. So we need 25% equity. So we should call 75%. 

What is the correct answer? If not correct answer, what is the correct way of approaching this situation. Do we go with our pot odds or do we want to decline him an autoprofit (playing GTO). 

Next question.

2)

If Villain were to open only 50% of BTNs (instead of 100%), do we still defend the same amount (given that A or B) might be correct BECAUSE our cards/ our top and bottom of our range is more important than Villains range (at least thats what I heard) bevause we play GTO. My problem is he now actually plays tighter. Do we still (if A was correct) say "No boy, no autoprofit on me, I still defend my X%." ?

Hope some of you guys understand what I mean. If not feel free to ask what I mean with certain phrases. 

Thank yo so much.