SORRY, YOU ARE WRONG.
The answer is false. Coverage isn’t automatic. Some insurers include coverage for sewer and drain backup as part of the standard homeowners policies. Others do not, but may sell the coverage as a separate endorsement. Ask your insurance agent or company whether you are covered. And, even if you are covered, take steps to protect against the mess caused by a backup:

Make sure gutter downspouts extend some distance from the house, to carry water away from basement walls

Grade your yard so that it slopes away from the house

Install a sump pump

If this is a persistent problem, install an anti-backflow device to prevent backup