Question

Which of the following is a plant growth regulator?

• A. Auxin
• B. Cytokinin
• C. Gibberellin
• D. All of these Correct Answer: (D) All of these

Hint:

To easily master the five primary Plant Growth Regulators for your biology exams, split them into two clear functional groups: 1. The Promoters (Growth Boosters): Auxins, Gibberellins, and Cytokinins. 2. The Inhibitors (Stress Responders): Abscisic Acid (ABA) and Ethylene. This functional breakdown helps you spot them instantly in any multiple-choice list!

Answer 1

The Correct Option is D

Step 1: Know what a growth regulator is.
A plant growth regulator is a small chemical made by the plant in tiny amounts. It controls things like growth, flowering and ripening. These are also called plant hormones.

Step 2: Look at each name.
Auxin, cytokinin and gibberellin are all well known plant hormones. Each one guides some part of plant growth.

Step 3: Decide the answer.
Since all three given names are growth regulators, the right choice is all of these.

Step 4: Final choice.
The answer is option 4.
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