Correct Answer: Russian Social Democratic Workers' Party — 1890
Subject: 2025
Explanation: <b>Key Fact</b><br>The Russian Social Democratic Workers’ Party — 1890 is the mismatched pair marked.<br><br><b>Additional Info</b><br>Topic: Russian Revolution. The correct option is <b>A</b> — Russian Social Democratic Workers' Party — 1890.<br><br><b>Why the other options are wrong</b><br><b>Option B</b>: Russian February Revolution — 1917 — not the option marked correct for this question.<br><b>Option C</b>: Socialist Revolutionary Party — 1900 — not the option marked correct for this question.<br><b>Option D</b>: Bloody Sunday — 1905 — not the option marked correct for this question.<br><br><b>Exam Trick</b><br>Identify the exact concept tested, then eliminate options that contradict the definition, formula, chronology or fact in the question.<br><br><b>Final Answer</b><br>Option A — Russian Social Democratic Workers' Party — 1890.