Your Google Account has been suspended!! Suddenly I got this email from Google. I was worried, All my Internet marketing and earning account are linked to this email? So what now? How to get back Google suspended account? So many questions in my mind. This was a terrible horror story when I read the email. 
Honestly, I didn't do anything which can be costly for this. Take a look at the email with snaps below:

Your Google Account has been suspended.

Hi ______,
Google has suspended your Account, ___________@gmail.com, because of a violation of our Terms of Service.
If you think this is a mistake, you can try to recover your account, by following these instructions. (a link)
All information associated with your suspended account will eventually get deleted unless successfully appealed.
Best,
The Google Accounts team

Did you know you can make money with Google AdSense without sending money? Also, you can get you AdSense account suspended. 

If Google banned your website, then it's time to recover it. Check out this tutorial. 

And now here is the snap of the horror email: Your Google Account has been suspended!

I got this email to my secondary email which was linked to the primary recovery option. 
You might be worried if you are facing the same issue. But I was looking for solutions. Had to search a lot on the web, but the web is full of fake information, and it was hard to find the real solutions.
So now come to the point:

Why Google Account Has Suspended?

Google treats policy violations and invalid activity very seriously in order to protect the users, publishers, and advertisers who make up our advertising ecosystem. While we usually notify publishers and take action for policy and invalid activity at the site level, there may be times when we will need to suspend or disable accounts due to policy violations or invalid activity.

The quoted answer is given by Google.com. If you wish to continue or want to get back your Google account, you must have to follow the Google TOS! Read it carefully.

Reset a Google Account suspension

If you are suspended by automatic system spam detector, Then you should not be worried. You can easily get back your account in basic steps.

Here how to recover suspended Google account:

1. Open Google login page via Gmail
2. Enter your email address in the provided field & Enter
3. Enter Your Password
4. Now Google will ask you to verify account via Mobile Number.
5. Enter your phone number registered with the account or a new mobile number
6. You will be sent a PIN to your Phone Number.
7. Enter the one PIN in the box provided and you will be prompted to a new page which will allow you to Log in Again.
8. Now Simply Enter Your Email again
9. Enter Your password. Hit the button ENTER
10. OMG! You are Logged into your Google Account! Congratulations!!

However if you really need more help or you can't do this, you can take help from your friends. By the same steps. But unfortunately, if you are unable to take help from your friends or family then here is the Google Help Line Number: 1-888-499-5526

Before calling them, be prepared with all question and answers they might ask you. Such as:

1. Your Google Account username
2. Your Name
3. Date of Birth according to the associated Google Account
4. Last successful login date
5. Most conversational email ID and so on...

However, Google has provided us more information on this account suspension related issue: Below are a quoted text from google:

You can't follow the instructions here to restore a user whose entire account has been manually suspended by an administrator. To do that, see Restore a suspended user. You also can't restore a user who has an abusive account status. 

To avoid this type of suspension from Google, Be sure your account is verified with a mobile number and you have stated a security question to your account. 

I hope this will help you.
Thanks