User cannot make duplicate entry because of the following property
Tap an option to check yourself.
Answer: A) Indexed
In MS Access, setting a field's Indexed property to Yes (No Duplicates) prevents users from entering duplicate values in that field.
MS Access मा कुनै Field को Indexed Property लाई Yes (No Duplicates) राखेपछि उक्त Field मा एउटै Value दोहोर्याएर राख्न मिल्दैन।
उदाहरण: विद्यार्थीको Roll Number Field मा 101 एकपटक राखिसकेपछि अर्को Record मा फेरि 101 राख्न पाइँदैन।
Exam Tip: Duplicate Entry रोक्न = Indexed → Yes (No Duplicates)।