Question
Biology Question on Plant Growth Regulators
One hormone hastens the maturity period in juvenile conifers, a second hormone controls xylem differentiation while the third increases the tolerance of plants to various stresses and they are respectively
A
Auxin, Gibberellin and Cytokinin
B
Gibberellin, Auxin and Cytokinin
C
Gibberellin, Auxin and Ethylene
D
Gibberellin, Auxin and ABA
Answer
Gibberellin, Auxin and ABA
Explanation
Solution
Spraying juvenile conifers with gibberellins hastens their maturity period, thus leading to early seed production. Auxin controls xylem differentiation. Abscisic acid (ABA) increases the tolerance of plants to various kinds of stresses therefore, is also known as stress hormone.