world leader
... that Nigeria is the world leader in cassava production?
... that <a href="./Nigeria" id="mwD7c" rel="mw:WikiLink" title="Nigeria">Nigeria</a> is the <b id="mwD7g"><a href="./Cassava_production_in_Nigeria" id="mwD7k" rel="mw:WikiLink" title="Cassava production in Nigeria">world leader</a></b> in <a href="./Cassava" id="mwD7o" rel="mw:WikiLink" title="Cassava">cassava</a> production?