google email meeting invite does not show response icons

I received a google meeting invite email and when viewing the email, it does not show the response icons (Yes, Maybe, No).  So I’m unable to respond via the email.

I’m running version: 7.1.32088.0

When I go to the Calendar I see the meeting and can right click to (Accept, Decline, Tentative).

How can I Accept, Decline, Tentative through the email (and also have the option to respond with a reply)? 

Here is what the email looks like in eM Client (notice that is has "You are neither an organizer nor attendee of the scheduled item)

Here is the same email in google web mail.

You only get the accept/tentative/decline options if the organizer has set your attendance as required. If your attendance is optional , you won’t get the option.