Concept:
Horticulture deals with fruits, vegetables, flowers, spices, plantation crops and ornamental plants.
Step 1: Check Assertion.
Horticultural crops provide vitamins, minerals, antioxidants and fibre. They help in improving health and quality of diet.
\[
A \text{ is correct}
\]
Step 2: Check Reason.
The reason says horticulture causes deterioration of land value and purchasing power. This is incorrect. Horticulture generally improves land value, income generation and employment opportunities.
\[
R \text{ is incorrect}
\]
Step 3: Final conclusion.
Assertion is correct but Reason is incorrect.
\[
\therefore \text{Correct Answer is (C)}
\]