Which plant hormone is primarily responsible for stem elongation and phototropism?
A
Cytokinin
B
Gibberellin
C
Ethylene
D
Auxin
Correct Answer: Option D — Auxin
Explanation:
Auxin is a plant hormone that regulates growth by promoting cell elongation, particularly in stems. It also controls phototropism, causing p...
Auxin is a plant hormone that regulates growth by promoting cell elongation, particularly in stems. It also controls phototropism, causing plants to bend toward light sources by stimulating faster growth on the shaded side.