My own.

It’s cliché but listening to my gut typically works out

On what?
Different people have different bodies of knowledge and experience. Their expertise on one question doesn’t transfer to another.

That OP always has an agenda. Doesn’t matter which OP but there is always one.

Honestly, it depends on what we’re talking about

I trust my nerd friend’s opinions on computers, and I trust my car friend’s opinions on cars, but probably not so much the other way around.

No single person knows everything, and trusting any single person completely about everything is foolish.

My spouse’s.

David Attenborough’s.

I trust the opinions of open minded and wise scientists the most. The people that should IMO have been our leaders instead of self serving politicians.

No one’s. Not even mine. Everyone is an idiot. Especially me.

Hank Green, and Alec from Technology Connections. Wildly different energy levels, but broadly speaking I trust them to do their homework or to outright say they haven’t.

Greta Thunberg

I don’t trust anyone’s opinion unless it’s based on sound evidence and repeatable results and even then, I’ll only trust the opinions of those who are willing to change their opinion based on new knowledge. So, given that, I’ll trust my young kids opinions on things they have researched and learnt about, or a doctor’s opinion if it’s on something they’re knowledgeable about, and my own in areas where I’m an expert.

How MUCH I trust them is a different thing. If it’s something that doesn’t really affect me if it’s not 100% accurate…meh

Yours

My wife mostly. Followed by myself.

In general my brother. He has schooling equivalent to my own and we both have interests and specialties that can converge a bit but also complement each other. Basically I like to discuss things with him because he both can get things im talking about but also may have a perspective or knowledge beyond my own. I think he feels the same but who knows. He seems to call me to talk about things as much as I call him.

I trust no one.