Which one of the following pairs is not correctly matched?

Which one of the following pairs is not correctly matched?

Positively phototropic : Shoot
Positively geotropic : Root
Chemotropic : Pollen tube
Hydrotropic : Flower
This question was previously asked in
UPSC CAPF – 2021
Tropisms are directional growth responses of plants to external stimuli. They are named based on the type of stimulus and the direction of growth (positive if towards the stimulus, negative if away).
Positively phototropic growth means growth towards light (e.g., shoots). Positively geotropic growth means growth towards gravity (e.g., roots growing downwards). Chemotropic growth is a response to chemical stimuli (e.g., pollen tube growing towards the ovule guided by chemical signals). Hydrotropic growth is a response to water (e.g., roots growing towards water). Flowers are reproductive structures whose position and development are influenced by factors like light (photoperiodism for flowering) and hormones, but ‘hydrotropism’ is not a primary or characteristic tropic response of flowers themselves. Roots exhibit positive hydrotropism.
Other types of tropism include thigmotropism (response to touch) and thermotropism (response to temperature). The statement ‘Hydrotropic : Flower’ is the incorrectly matched pair as hydrotropism is characteristic of roots.