Question - on communication

I am pretty sure I have found an error

Question :

You are currently managing a team of five auditors and conducting an IT audit project for a customer on their premises. Due to technical reasons you and your team fcannot use your business email accounts during the project. You device to use Blahoo web mail in the order to communicate with each other. The use of the Blahoo web mail is an example of ?
A. Formal communication
B. Interactive communication
C. Push communication
D. Pull communication

ANSWER : D ) PULL Communication.

I understand the explanation where it said that people have to consult their mail so it’s pull..

BUT, PMBOK doesn’t said this so I think this is wrong !!

PMBOK Said Email = PUSH

Push communication. Sent to specific recipients who need to receive the information. This ensures
that the information is distributed but does not ensure that it actually reached or was understood by the
intended audience. Push communications include letters, memos, reports, emails, faxes, voice mails,
blogs, press releases, etc.

This is cornelisu fitcher i think ... It seems complicated to me, i guess you can safely ignore this and move on.

thanks