The enrollment age for Medicare is ______, at which time one is automatically enrolled in Part(s) ______ at no cost.

 a. 67; A 

b. 67; A & B

 c. 65; A & B

 d. 65;

How many quarters of coverage under the Social Security system must one earn to be considered "fully insured" for retirement benefits? 

a. 40

b. 20 

c. 10

d. 50