The Badminton World Federation's 2019 report records Sindhu's women's singles gold at the World Championships in Basel. BWF identifies it as India's first badminton world-championship gold. This title is a world championship in a specific sport and discipline, not an Olympic gold. Basel is the host city; Rio and Tokyo are separate Olympic host references. Exam writers often swap a correct athlete with the wrong tournament because both are major international events.
Use a two-column contrast: Rio silver and Tokyo bronze are Olympic Games results; Basel gold is a BWF World Championships result. The governing body and championship name tell you which medal list to consult. “World champion” can refer to many sports and time controls, so even this phrase should be completed as “2019 badminton women's singles world champion.” It says nothing by itself about a current world ranking, which can change.
Worked example: Sindhu's 2019 BWF World Championships gold in Basel is a world-championship title, not an Olympic gold medal. Compare competition level before choosing an answer. A world-championship medal and Olympic medal can both be major international achievements but come from different organisers and result archives. Preserve the city and year only if the question calls for them.
Active recall: Why is the statement “Sindhu won Olympic gold in Basel” wrong even though the person and colour sound familiar?