Why is the local time difference between India's eastern and western ends administratively important?

Correct answer: It shows the need for time coordination across regions

The governing concept is the relationship between east–west extent, longitude, and local time. Earth rotates 360 degrees in about 24 hours, so places separated by longitude experience different local solar times; roughly 1 degree of longitude corresponds to four minutes. India’s eastern and western ends therefore have a substantial local-time difference. For administration, transport, schools, offices, broadcasting, and communication, a common standard time is needed. Option A is correct because it identifies this need for coordination and explains why India uses Indian Standard Time based on a selected standard meridian. Options B, C, and D concern coastline, hemispheres, and relief, none of which is caused by local-time differences.