Error spotting (case after prepositions): Identify the erroneous part (A/B/C) — mark D if there is no error — 'Since we are friends / there should be no secret / between you and I. / No error.' Focus on objective-case pronouns after prepositions.

Given data

• A. Since we are friends
• B. there should be no secret
• C. between you and I.
• D. No error.

Concept/Approach (pronoun case)
A preposition ('between') must be followed by object pronouns. Therefore, 'between you and me' is correct, not 'I'.

Correction
'…between you and me.'

Common pitfalls
Overcorrecting to 'you and I' in all contexts; remember prepositions demand object case.

Final Answer
C — Use 'between you and me.'