映射器只允许写入具有公开setter的属性，哪个检查表达了这项契约？

映射器只允许写入具有公开setter的属性，哪个检查表达了这项契约？

1. `property.SetMethod?.IsPublic == true`
2. `property.CanWrite`
3. `property.GetMethod is not null`
4. `property.MemberType == MemberTypes.Property`