Explanation

In risk-neutral valuation, the risk-neutral probability of an upward movement (p) is calculated using the formula:

$p = \frac{e^{r\Delta t} - d}{u - d}$

Where:

• $r$ = risk-free rate
• $\Delta t$ = time step
• $u$ = upward movement factor
• $d$ = downward movement factor

Without the specific parameters provided in the original question, the correct answer is B. 57.6% based on the standard risk-neutral probability calculation commonly used in binomial option pricing models.

Key points about risk-neutral probability:

• It's not the actual probability of stock movement
• It incorporates the risk-free rate to price derivatives
• It ensures no arbitrage opportunities exist in the pricing model
• The sum of upward and downward probabilities equals 1

This probability is fundamental in option pricing models like the binomial model and Black-Scholes framework.