Which of the Inputs in the Black-Scholes Option Pricing Model

Multiple Choice

Which of the inputs in the Black-Scholes option pricing model are directly observable?

A) The price of the underlying security
B) The risk-free rate of interest
C) The time to expiration
D) The variance of returns of the underlying asset return
E) The price of the underlying security, risk-free rate of interest, and time to expiration