You need to prepare the certificate required for the planned deployment

You plan to deploy 20 Client Access servers that will have Exchange Server 2013 installed.
You need to prepare the certificate required for the planned deployment. The solution must ensure
that the same certificate can be used on all of the Client Access servers.
What should you do first?

A.
From the Exchange Admin Center, create a new certificate request.

B.
On each Client Access server, start the Certificates console and run the Certificate Import Wizard.

C.
On all of the Client Access servers, delete the default self-signed certificates.

D.
On one of the Client Access servers, run the Remove-ExchangeCertificate cmdlet.

Explanation:
You can use the EAC to generate certificate requests that work with most certificate issuers.
Note:
To prevent clients from receiving errors regarding untrusted certificates, the certificate that’s used
by your Exchange server must be issued by someone that the client trusts. Although most clients can
be configured to trust any certificate or certificate issuer, it’s simpler to use a trusted third-party
certificate on your Exchange server. This is because most clients already trust their root certificates.
There are several third-party certificate issuers that offer certificates configured specifically for
Exchange.