Explanation:

Let’s break this down:

- USA spends way more on health as a percentage of GDP—think around 16–18%. It’s famously high.

- China’s percentage is much lower, roughly 5–6%, but higher than India or Sri Lanka.

- India puts in about 3% of GDP, maybe a touch less, on healthcare.

- Sri Lanka? Even less—often under 2%, sometimes close to 1.5%.

So, the country with the lowest health expenditure as a share of GDP from the options you gave is definitely Sri Lanka.

Option 4: Sri Lanka