The correct formula for profile drag coefficient over the finite wing is_______

• A. cd=\(\frac {D_f+D_P}{Sq_∞}\)
• B. cd=\(\frac {D_P}{Sq_∞}\)
• C. cd=\(\frac {D_f}{Sq_∞}\)
• D. cd=\(\frac {D_f+D_P+D_i}{Sq_∞}\)