The correct answer is B - "The small capitalization minus big capitalization risk factor" (SMB).

Fama-French Three-Factor Model Components:

1. Market Risk Factor - Excess return of the market portfolio over the risk-free rate
2. Size Factor (SMB) - Small Minus Big: Returns of small-cap stocks minus returns of large-cap stocks
3. Value Factor (HML) - High Minus Low: Returns of high book-to-market stocks minus returns of low book-to-market stocks

Why other options are incorrect:

• A: Investment Growth is not part of the original three-factor model (though it appears in later five-factor models)
• C: Winners minus losers is the momentum factor (WML), which was added later in the Carhart four-factor model
• D: Inflation is not a specific factor in the Fama-French model

The Fama-French three-factor model extends the CAPM by adding size and value factors to better explain stock returns.