Problems with the menu

On my Homepage I have a problem with the index.html.

Only on the "Home" Site are two aspects in the menu are shown as "active"
> "Startseite" and "Aktuelles"

http://juhasz.de/

How I can fix that?
I took a look in the source code:

There is the class by "Aktuelles" with
<li id="menu-item-130" class="menu-item menu-item-type-post_type menu-item-object-page current_page_parent menu-item-130"><a href="http://www.kaufhaus-juhasz.de/preview/wordpress/?page_id=11">Aktuelles</a>

All other Menu points have´n that.
<li id="menu-item-155" class="menu-item menu-item-type-post_type menu-item-object-page menu-item-155"><a href="http://www.kaufhaus-juhasz.de/preview/wordpress/?page_id=25">Geschichte</a></li>

In which file on my ftp I can fix that?
Which php?

Or is it in a folder
"wp-admin"
"wp-content"
"wp-includes"

I cant find the file

 

Hello,

Go to
Settings > Reading
and follow the instruction as shown in image given below




This will solve your issue.

 

Thank you! It works!