If $u=\log \tan \left(\frac{\pi}{4}+\frac{\theta}{2}\right)$, then $\cosh u=$

• Correct answer
  A

  $\sec \theta$
• B

  $\tan \theta$
• C

  $\operatorname{cosec} \theta$
• D

  $\cot \theta$

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