Which of the following is NOT a naturally occurring auxin?a) Indole 3-acetic acid (IAA)b) Indole 3-butyric acid (IBA)c) Phenyl acetic acid (PA

• A. Indole 3-acetic acid (IAA)
• B. Indole 3-butyric acid (IBA)
• C. Phenyl acetic acid (PAA)
• D. 2,4-D