RegisterOptions.cs

public static void RegisterOptions(this ContainerBuilder builder)
{
  builder.RegisterGeneric(typeof(OptionsManager<>))
    .As(typeof(IOptions<>))
    .SingleInstance();
  builder.RegisterGeneric(typeof(OptionsMonitor<>))
    .As(typeof(IOptionsMonitor<>))
    .SingleInstance();
  builder.RegisterGeneric(typeof(OptionsSnapshot<>))
    .As(typeof(IOptionsSnapshot<>))
    .InstancePerLifetimeScope();
}