If you are on holiday, will you answer your work related phone calls?

I would response to my secretery's calls or my CEO's calls. After all, how shall I charge my batteries and  empty my brain in order to be more efficient to my job duties in the future?

Yes, I will answer work related calls. Because I get my daily bread from that organization.

After knowing that you will be away for holidays and you still get calls from your office or client, means you have not organized your last minute tasks/work well before going on holidays. You should be completing all your pending work and to serve your best to organization, should be delegating it to your reporting manager or colleagues to help you and your customers while you are on holidays. 

And if you are not doing that, your company can tolerate you nonetheless your customers will not tolerate as your salary comes from your consumer’s money only. So just imagine the loss of your negligence of not preparing everything before you are going on holidays.  

I would definitely respond to work related phone calls as I can understand that people would reach out to me only when they really need it. Also, there could be times where the other person is not aware about my being on vacation and in that case I would politely redirect them to my team or Manager or any other concerned person.

Yes, I will as opportunities do no wait.

My personal past experience, I used to.....I will attend except certain known cases.

As a Business Development Manager you are representing your Organization all the time. It does not matter whether you are on holidays or working. Clients are not aware that its your holiday period going on, so expect business calls any time. Working on the post of Business Manager my personal experience of finding business could be any place, its you who need to find your target people,make decision and briefly present your  product and make a contact.