Which of the two students is best?

[Tan Elaine]

It is not wrong to say "Which of the two students is the best." Is this correct? I was taught that I should use 'better'.

I am sorry to say that it should be a simple question but the above advice baffles me.

Thanks.

[Raymott]

It is not wrong to say "Which of the two students is the best." Is this correct? I was taught that I should use 'better'.

I am sorry to say that it should be a simple question but the above advice baffles me.

Thanks.

Yes, some people will tell you that you shouldn't use the superlative form when talking about only two things, eg:
"Which of the brothers is the elder?"
"Which of the two is better?"
"Which of the two girls is [the] prettier?"
...
But few people bother with this rule these days.