I don´t understand this question

[aioria]

Certain zoologists regard crows and ravens are the most intelligent of birds

correct answer is "B"

I dont understand why
I also don´t understand the part "Certain zoologists regard crows and ravens "
what does this sentence mean?
??

[vreddy]

regard crows and ravens AS the most intelligent of birds

[bee]

Hi, aioria!
There exist an expression "to regard smth or smb as". For example: They regard him as a hero. = They consider him a hero.
Good luck!

[Idiot]

Originally posted by bee

Hi, aioria!
There exist an expression "to regard smth or smb as". For example: They regard him as a hero. = They consider him a hero.
Good luck!

Thanks all
You make me remember this structure

[aioria]

I got it !!
thank you both !
Now I understand =)