Which one of the following longitudes determines the Indian standard time? [2009-I]

• A. \[85.5{}^\circ \text{ }E\]
• B. \[86.5{}^\circ \text{ }E\]
• C. \[84.5{}^\circ \text{ }E\]
• D. \[82.5{}^\circ \text{ }E\]