Which of the following properties can be insured under a flood insurance policy?

A mobile home on a foundation in a mobile home park can be insured under a flood insurance policy because it is classified as a building for insurance purposes. The National Flood Insurance Program (NFIP) provides coverage for residential structures that are affixed to a permanent foundation. This means that the mobile home, having been placed on a foundation, meets the criteria set by the NFIP for insurable properties.

In contrast, the other options do not qualify for flood insurance because they do not meet the NFIP's definition of a building. A septic tank is considered a component of a property but not a structure that qualifies for flood coverage. A flower garden is not deemed a building and therefore is not insurable under flood policies. An open-sided park pavilion, while a structure, typically does not have four walls, which is a requirement for coverage under NFIP standards. Therefore, the mobile home is the correct choice for insurability under flood insurance policies.