Final answer:
Al-Kindi, the first person to publish a way of cracking Caesar's encryption scheme, used frequency analysis as his method of solution.
Step-by-step explanation:
The subject of this question is History. Al-Kindi, the first person to publish a way of cracking Caesar's encryption scheme, was a historical figure. His method of solution relied on analyzing the frequency distribution of letters in the encrypted text. He observed that certain letters appeared more frequently than others and used this information to decipher the code.