Buff orphington hen or roo?

[Kgajewski]

first picture is subject in question
Second and third pictures are chickens I bought at the same time.
The subject chicken has been a very curious chicken since I brought them home (1 week of age) it's comb is bigger and redder and it's a bit taller than the other two, but there has been no vocal give away yet.
They were guaranteed to be hens...​

Thanks in advance for any help.

 

[ADuckOnQuack]

Top pic a rooster
And bottom one a pullet

 

[Kgajewski]

Thanks