Correct answer: (a) Hubballi
Explanation
- A
Hubballi
(a) Hubballi. In August 2020 the Railway Museum / heritage museum at Hubballi (South Western Railway) was dedicated to the nation. Official key.
- B
Mysore
(b) Mysore. Mysuru has railway heritage interest, but the August 2020 dedication named in the question is Hubballi.
- C
Silvasa
(c) Silvasa. Silvassa is not the 2020 railway-museum dedication site.
- D
Chittaranjan
(d) Chittaranjan. Chittaranjan is the locomotive works town; it is not the August 2020 museum dedication.
Summary. Official key is (a) Hubballi. The 2020 dedication was at Hubballi in Karnataka under South Western Railway. Mysuru, Silvassa and Chittaranjan are other railway or industrial names and do not match that August event. National Rail Museum itself remains at New Delhi (Chanakyapuri), a separate older institution.