How would you write a tax_query to find posts that belong to either the 'news' category or have the tag 'featured', using the correct relation?
A'tax_query' => [ 'relation' => 'NOT', [ 'taxonomy' => 'category', 'field' => 'slug', 'terms' => ['news'] ], [ 'taxonomy' => 'post_tag', 'field' => 'slug', 'terms' => ['featured'] ] ]
B'tax_query' => [ 'relation' => 'AND', [ 'taxonomy' => 'category', 'field' => 'slug', 'terms' => ['news'] ], [ 'taxonomy' => 'post_tag', 'field' => 'slug', 'terms' => ['featured'] ] ]
C'tax_query' => [ [ 'taxonomy' => 'category', 'field' => 'slug', 'terms' => ['news', 'featured'] ] ]
D'tax_query' => [ 'relation' => 'OR', [ 'taxonomy' => 'category', 'field' => 'slug', 'terms' => ['news'] ], [ 'taxonomy' => 'post_tag', 'field' => 'slug', 'terms' => ['featured'] ] ]
