Spelling selection — Choose the correctly spelled security term used in reports and news: identify the accurate form of "Surveillance" for formal English writing and exams.

Given data

• Word: "Surveillance" (monitoring/observation).
• Options: Survaillance; Surveillance; Survellance; Surveilance

Concept/Approach
French-derived word with the core sequence "veil" inside: sur + veil + lance → "surveillance".

Step-by-step reasoning
Surveillance — correct spelling.Survaillance — incorrect double "ai".Survellance — wrong "ve-ll" placement and missing "i".Surveilance — missing the second "l".

Verification/Alternative
All major dictionaries standardize on "surveillance".

Common pitfalls
Misplacing vowels "ei/ai" and doubling incorrect consonants.

Final Answer
Correct spelling: Surveillance.