Sentence Correction

The EU announced that cod and macakarel are the only fish that exceeds/exceed


i am confused with exceed/exceeds ...


after who/that it is generally the verb of the subject before that.

Here it is fish...so i thought exceed will be correct.


Kindly explain with explains

exceed is correct here.

The sentence says "cod and mackerel are the only fish".

While we could debate whether the only is used correctly here, one thing is clear.

Cod and mackerel is plural, and are is plural. So fish, which word can be singular or plural, is plural here.

So fish requires the plural form of the verb, and so exceed, which is the plural form, is correct.