Can you help with this question?

Which statement is not true when a
teacher exhibits defensive behavior
during a hostile conversation with
a parent?

1. it may lead to an explosive
situation.

2. it will tend to escalate tension.

3. it suggests to the parent that
their assumptions are correct.

4. it suggests to the parent that
the teacher is a professional
who is capable of supporting
parents.

I know 1 and 2 are true.
Would the correct answer for the one
NOT true be #4?

Yes, I think you're right to choose #4.

I have never been afraid to escalate tension when it is in the benefit of the student. I have never been afraid to confront a parent when it is in the interest of the student. I have never been afraid to tell a parent NO when it was in the interest of the student.
I suspect you will not find these ideas in conjunction with your teacher training, but remember them. Kids come first. If you know what you are doing, and why, don't be afraid to step up.
Answer 4 is probably the best, but it really depends on what is meant be defensive.
I asked a young teacher this year to have a parent conf the first week to tell her of a parent situation with one of my foster kids. The teacher wouldn't meet until the principal was available. That to me is really defensive. I was surprised they didn't bring a school board lawyer, and all I was doing was giving info. So be professional, keep the goal of making the kid an educated person. You don't have, nor need, to let others dictate how you do it.