This is 5th PA based phishing call I've had in two weeks. I never answer and they never leave messages. Dollars to donuts, this is either a telemarketer or bill collector testing phone numbers to see if they're live. My recommendation is not to answer.
Checked this number on "whocalld.com" and found them to be MDS Communications.
They are a telephone fundraising company with various clients. Further research shows their financials reporting that they keep more than 60% of the money donated through their service.
All their clients may not have the same deals so some may be getting back very little.
After checking a charity's rating on sites like Charity Navigator, Charity Watch, ECFA, etc., and you still want to support a charity, deal with them directly.
Number is now blocked!