A program consisting of 323 instructions is executing on a simple processor. Each instruction takes 4 cycles to complete, with a clock rate of 339 KHz. How long will it take to execute the program? Give your answer in units of milliseconds with at least 1 decimal place of precision. 
A. 3.6 ms 
B. 4.1 ms 
C. 4.8 ms 
D. 5.3 ms