If the latus rectum through one of the foci of a hyperbola $\frac{x^2}{9}-\frac{y^2}{b^2}=1$ subtends a right angle at the farther vertex of the hyperbola, then $b^2=$

• A

  $4$
• B

  $16$
• C

  $25$
• Correct answer
  D

  $27$

Hence, the correct answer is option: 'D'.