I'll give you a question, please answer with step-by-step reasoning process.
Context: "The Star-Spangled Banner" was recognized for official use by the United States Navy in 1889, and by U.S. President Woodrow Wilson in 1916, and was made the national anthem by a congressional resolution on March 3, 1931 (46 Stat. 1508, codified at 36 U.S.C. § 301), which was signed by President Herbert Hoover.\n\nQuestion: when did star spangled banner became national anthem?

March 3 , 1931
The relevant information to answer the above question is: "The Star-Spangled Banner" was recognized for official use by the United States Navy in 1889, and by U.

S.

President Woodrow Wilson in 1916, and was made the national anthem by a congressional resolution on March 3, 1931 (46 Stat.

1508, codified at 36 U.

S.

C.

§ 301), which was signed by President Herbert Hoover.

.

Therefore, the answer is March 3 , 1931