Sentence Correction

First post Great community...

I am going through Sahil's grammer notes and came up with a sentence based on them. Thus, no OA. Which one would be correct:

a)One of the doors that open wide is yellow.
b)One of the doors that open wide are yellow.
c)One of the doors that opens wide is yellow.

Pretty sure we need "open" rather than "opens" since doors is plural. Guessing we can go back to singular though - "is."

Therefore, i think its a.

What do you guys think?

l;

Thanks, and thanks for the response. Have you seen the examples below?

He is one of the persons who make money.
This is one of the cars that run on hydrogen.

According to the Notes, those are correct (I don't know how accurate the notes are but I assume they are pretty good...)

So using your logic it should really be "One of the persons who makes money?" and "One of the cars that runs on hydrogen?"

Let me know if you disagree with the example sentences in the notes...

720dreaming wrote:First post Great community...

a)One of the doors that open wide is yellow.
b)One of the doors that open wide are yellow.
c)One of the doors that opens wide is yellow.

Ok here is my take on these sentences

In the above sentences
'open' is being used for doors
so we should have

Noun----------------Verb
doors (plural) - open (plural)
door (singular) - opens (singular)

Now, part 2

the verbs 'is' and 'are' are used for ''One of the doors/door'' which is singular because it's in the "one of the X" form (which is singular)

so we have

Noun-------------------------------------Verb
One of the doors/door (singular) - is (singular)

So you should have -

One of the doors that open wide is yellow

that's what I was thinking...(btw the colors make it easy to understand what goes with what)

Nice explanation..

i believe there was a discussion on here that decided -

in a construction such as 'one of the Xs', if there is a 'that' or a 'who' after Xs, then the next verb (is / are) becomes plural. if there is no 'that' or 'who, then it stays singular.