Statement: Groundwater in the locality contains high levels of arsenic, making it dangerous to drink.\nCourses of Action:\nI. Immediately shift people living in the area to a different locality to avoid a catastrophic situation.\nII. Arrange for safe drinking water supply (e.g., treated piped water, tankers, community RO units).

Introduction / Context:
Arsenic-contaminated groundwater is a serious public-health hazard. Effective courses of action must prioritize immediate risk mitigation and sustainable safe-water access while considering feasibility and proportionality.

Given Data / Assumptions:

• Drinking groundwater locally is unsafe due to arsenic levels.
• Contamination is at the source; household boiling does not remove arsenic.

Concept / Approach:
Providing safe water (II) directly addresses the hazard via alternative sources and treatment (piped surface water, tanker supply, community RO/activated alumina filters, blending within safe limits). Mass relocation (I) is drastic, logistically complex, and rarely the first-line response; it disrupts livelihoods and social networks and is only justified if remediation and safe supply are impossible in reasonable time.

Step-by-Step Solution:
1) Implement II: establish immediate safe-water points and medium-term piped solutions; communicate do-not-drink advisories for contaminated tubewells.2) Keep relocation as a last resort for pockets where safe supply cannot be ensured despite best efforts.

Verification / Alternative check:
Public-health interventions worldwide prioritize risk communication and provision of safe alternatives over relocation except in extreme, unmanageable contamination scenarios.

Why Other Options Are Wrong:
Only I overreacts; Either/Both inappropriately elevate relocation to parity with the practical solution.

Common Pitfalls:
Assuming relocation is the default remedy; overlooking that arsenic is removable only with specific treatment, not by boiling.

Final Answer:
Only II follows.