Describe a "high-deductible health plan" (HDHP).

A high-deductible health plan (HDHP) is defined as a health insurance plan that features higher deductibles than traditional insurance plans, paired with lower premiums. This design allows insured individuals to save on monthly costs while also requiring them to pay more out-of-pocket before insurance coverage begins.

The primary purpose of an HDHP is to encourage consumers to engage more actively in their healthcare spending decisions, which can lead to more cost-effective choices. Many HDHPs are paired with Health Savings Accounts (HSAs), which enable individuals to set aside pre-tax money to cover eligible medical expenses, further adding a layer of financial flexibility for those who enroll in such plans.

When analyzing the other options, it is clear that they do not accurately capture the essence of what an HDHP is. Plans with low deductibles and high premiums would not qualify as high-deductible plans. Similarly, while HDHPs may provide coverage for serious health issues, they are not limited to catastrophic coverage alone; they cover a wide range of medical services after the deductible is met. Lastly, plans with no deductibles at all would contradict the fundamental characteristic of an HDHP, which is defined precisely by having higher deductibles.