To answer this question, we need to identify the person who said the inspirational line: "I walk slowly, but I never walk backward."
Let's go through each option to determine who said this line:
Option A) William Shakespeare - This option is incorrect because there is no evidence or historical record that attributes this line to William Shakespeare.
Option B) George Bernard Shaw - This option is incorrect because there is no evidence or historical record that attributes this line to George Bernard Shaw.
Option C) Abraham Lincoln - This option is correct. Abraham Lincoln, the 16th President of the United States, is credited with saying this line. It reflects his determination and perseverance.
Option D) Franklin D. Roosevelt - This option is incorrect because there is no evidence or historical record that attributes this line to Franklin D. Roosevelt.
The correct answer is option C) Abraham Lincoln. This option is correct because Abraham Lincoln is the one who said the inspirational line: "I walk slowly, but I never walk backward."