In which of the following activities are Indian Remote Sensing (IRS) satellites used?

Answer: (a) 1, 2 and 3 only

The answer is (a). IRS satellites are earth-observation satellites, and their data serve agriculture, water resources and mineral prospecting, so items 1, 2 and 3 fit. Telecommunication is handled by the INSAT/GSAT communication satellites, so item 4 is wrong. That rules out both (b) and (d), the only options containing item 5. Item 3 being correct then picks (a) over (c).

• ✓ 1. ISRO says IRS data are used for agriculture. Crop-area and crop-condition assessment is a core use of remote sensing.
• ✓ 2. IRS data feed water-resources applications. ISRO's earth-observation services include groundwater prospects and groundwater quality information.
• ✓ 3. ISRO explicitly lists mineral prospecting among the applications of IRS data.
• ✗ 4. Telecommunication is the job of the INSAT/GSAT geostationary communication satellites, not of the sun-synchronous IRS series.
• ✗ 5. Traffic studies are not among the applications ISRO lists for IRS data. Both options that include this item, (b) and (d), also include item 4, which is wrong, so item 5 cannot be part of the answer.
• ✗ (d) This option is the tempting one because it looks all-inclusive. It fails because it includes telecommunications.

Remember · IRS series = earth observation (agriculture, water, minerals, forestry, urban planning, disasters). INSAT/GSAT series = telecom, broadcasting and weather.

Question: UPSC Civil Services (Preliminary) 2015, General Studies paper. Explanation: Minimalist IAS, checked 25 Oct 2026 (how we verify). · Report an error