Among the following cities, which one lies on a longitude closest to that of Delhi?

Delhi lies at about 77°13′E. Bengaluru is at about 77°35′E, roughly 0.4° away, which makes it the closest longitude among the four options. So A (Bengaluru) is correct.

• Hyderabad (B) is at about 78°29′E, about 1.3° east of Delhi. Wrong.
• Nagpur (C) is at about 79°05′E, nearly 2° east of Delhi. Wrong.
• Pune (D) is at about 73°52′E, more than 3° west of Delhi. Wrong.

The core concept here is that longitude is an east-west coordinate, and only the east-west gap matters. Its relevance to the syllabus is that 1° of longitude equals about 4 minutes of local time, which is why India's 82°30′E meridian (IST) matters for time-zone debates. Keep that in mind for Mains questions on India's single time zone.

Trap: aspirants judge by map distance or by latitude, or assume Hyderabad or Nagpur is 'central' and so closer. Check the degree values instead.