Is disease prevention by the government a pure public good or a private good? explain

NO

Explanation:

Streetlight is an example of public good. When I get the light from a streetlight, another person can also get the light from the same streetlight at the same time. It is indivisible. It is difficult to exclude someone from getting the benefit of a street light. (A wall and toll gate are needed to exclude but these are costly). It is non-excludable.

In addition to public goods, governments may provide pipe water supply, electricity, medical care, higher education, etc. These are not public goods since each of these services is divisible and excludable.

by knowing conditionality

explanation:

the third answer is correct.