BuddyPress.org

Just delete

<li<?php if ( bp_is_page( BP_HOME_BLOG_SLUG ) ) {?> class="selected"<?php } ?>><a href="<?php echo get_option('home') ?>/<?php echo BP_HOME_BLOG_SLUG ?>" title="<?php _e( 'Blog', 'buddypress' ) ?>"><?php _e( 'Blog', 'buddypress' ) ?></a></li>