Final answer:
Medicare Part A is the part that covers hospitalization costs such as inpatient care, and is most likely to cover the charges for Mrs. Miller's hospital stay after a heart attack.
Step-by-step explanation:
The Medicare Part that will most likely pick up the charges while Mrs. Miller is in the hospital after a heart attack is Medicare Part A. This part of Medicare covers hospitalization costs, which include inpatient care in hospitals, skilled nursing facility care, hospice care, and some home health care services. Individuals who are eligible for Social Security benefits can avail of this service, which is funded by payroll deductions along with contributions from employers. However, it should be noted that people are responsible for a deductible charge before Medicare payments kick in, as well as copayments for many hospital-related services, with no limits on total expenses one can incur.