The answer to this question was Option B.

But, can we not have either 2 angles obtuse and 2 acute…or all 4 of them equal 90? The answer would then be option D.

Not quite. The reason is that you can use vertically opposite angles properties.

The “All 4 of them equal 90” doesn’t work since 90 degrees isn’t obtuse. Can you show that three obtuse angles isn’t possible, either?

Oh alright.

So if we say ‘a’ is obtuse, then ‘c’ is also obtuse, which means that ‘b’ and ‘d’ have to be acute.

And, I realised my mistake about all of them being 90.

So to sum up, we could either have 2 obtuse and 2 acute or all 4 of them acute, which leads us to option B.

Thanks!