Applications of remote sensing: These techniques are usefully employed for which purposes?

Introduction / Context:
Remote sensing provides synoptic, repeatable, and multi-spectral observations of Earth. The data support decision-making in agriculture, forestry, water resources, urban planning, disaster management, and environmental protection. This question tests awareness of the broad utility of remote sensing.

Given Data / Assumptions:

• Satellite and aerial platforms deliver calibrated imagery at various spatial and temporal resolutions.
• Geospatial analyses transform imagery into thematic products.
• Stakeholders include resource managers, planners, and environmental agencies.

Concept / Approach:
Natural resource management uses vegetation indices, soil moisture proxies, and water-body mapping. Land-use/land-cover mapping leverages spectral signatures and time series to classify urban, agricultural, and natural classes. Environmental protection monitors deforestation, pollution events, coastal erosion, and air quality, often integrating time-series change detection.

Step-by-Step Solution:
Link resource management to biophysical retrievals (e.g., LAI, NDVI, evapotranspiration).Tie land-use mapping to supervised/unsupervised classification, object-based analysis, and machine learning.Connect environmental protection to monitoring illegal mining, fires, oil spills, algal blooms, and habitat loss.Since remote sensing supports all listed purposes, select the comprehensive option.

Verification / Alternative check:
Operational programs (e.g., national forest monitoring, agricultural advisories, coastal zone management) demonstrate each application area at scale.

Why Other Options Are Wrong:
Single-purpose options omit the multi-sector impact of remote sensing.Only military reconnaissance: Historically important but not the sole or dominant civil purpose.

Common Pitfalls:
Assuming remote sensing is too coarse or infrequent; modern constellations provide frequent, high-resolution coverage enabling timely decisions.

Final Answer:
All of these.