a) Describe the process that led to the Supreme Court's ruling on the challenge to the affordable care act

The constitutionality of the Act was challenged by states based on two main grounds: 1. The issue of individual mandate; and 2. Mandatory expansion of medicaid by states.

Explanation:

The Affordable Healthcare Act otherwise known as Obamacare was a health reform Act that came into force in 2010 under the Obama administration in the United States of America which made provision for affordable health insurance for every citizen of America, and also expanded the scope of eligibility for medicaid in the United States of America. The constitutionality/legality of the Act was challenged by a total of about 26 states of the United States of America particularly on the ground that the Act imposed sanctions on states which failed to expand the medicaid, and on the ground of individual mandate to purchase health insurance violated the original Clause.

However, concerning the issue of individual mandate to buy health insurance, the Supreme Court of America upheld the constitutionality of the ACA on the ground that the congress has the valid and constitutional power to impose tax.

On the other hand, on the issue of mandatory expansion of medicaid by states, the court stated that it was optional and not mandatory for states to chose to expand the medicaid, thereby declaring the mandatory medicaid expansion by states unconstitutional.