Write the expression in terms of the appropriate cofunction.

$\cos\left(\frac{19\pi}{45}\right)$

• A. $\cos\left(\frac{7\pi}{90}\right)$
• B. $\sin\left(\frac{4031\pi}{45}\right)$
• C. $\sin\left(\frac{7\pi}{90}\right)$
• D. $\cos\left(\frac{4031\pi}{90}\right)$